The value of a formal contract is recording agreements among all participants to ensure everyone understands what is expected. Obviously, a long written contract will make most players' eyes glaze over and kill the fun. Maybe just have a discussion about some things. If you have a widely fluctuating set of players coming and going, a written contract can help new players assimilate quickly.
A formal social contract covers all details of play. Specifically, it is an agreement to play a certain game, at a certain time and place, with certain people, in a certain way. In other words: what, when, where, who, why, and how.
What
- What game are we playing?
- What version of the rules?
- What house rules?
- Can house rules be introduced later? By what process?
When
- What is the game schedule? Weekly? Every other week? Monthly? Irregular?
- What are the exceptions to the schedule?
- What is considered "quorum" for a game? (Under what circumstances will you cancel a game?)
- What is the process for formally cancelling a game?
- How should players notify people if they cannot play? if they can play?
- What is the process for formally inserting an additional game outside of the normal schedule?
- How long do we play (per session)? Will that change often (extended games), or do we need to stop at a certain time?
- How long of commitment are you expecting? One game? Three games? A year? Forever?
- Is it cool to miss games? How often?
Where
- Where is the game hosted?
- Are hosting duties shared?
- What is the address of the place where we play? Got directions?
- Where do we park?
- What are the special rules of the house? (take off your shoes, don't let the cat out, etc.)
- What should people bring? (food, dice, books, miniatures, etc.)
- Will we eat during the game? Who brings the food? How is paying for delivery food handled?
Who
- Who is invited to play?
- Who is excluded from play?
- What is the process for inviting new members?
- What is the process for bringing a friend or significant other to a game?
- Are children or spectators or pets permitted as tag-alongs?
- What is the process for correcting poor player behavior?
- What is the process for expelling someone you don't like?
Why
- What is the point of play for this group?
- What is the general mood of play? (fun, serious, dark, etc.)
- What is the general theme of play? are there any special tropes?
- Is it okay for players (including the GM) to be competitive with each other? (up to killing each other's characters?)
- Are there any limits about game content ("lines and veils")?
How
- How do players create characters?
- How do players advance characters?
- What level of playing "in role" is expected of all players? What is too little? Too much?
- What is the expectation around character death? Under what circumstances can it happen or not happen?
- If a character dies, how does the player replace it?
- How do players integrate characters into the setting?
- How do players integrate characters into the game's situation or existing character group?
- What kind of play behavior is considered annoying?
Also take a look at Chris Chinn's Same Page Tool.
"A practical man can always make what he wants to do look like a noble sacrifice of personal inclinations to the welfare of the community. I've decided that I've got to be practical myself, and that's one of the rules. How about breakfast?" The Pirates of Ersatz, Murray Leinster
From your question I noticed a few things. Nominally, I completely agree with @mxyzplk's answer, so this should be in the way of an addendum.
It sucks to be the leader
In a RPG, it just completely sucks to be the leader. Most players when confronted with a plan, remember about fifteen percent of it for the first fifteen minutes. But they'll certainly remember when you deviate. Leaders get no additional responsibility and no perquisites, but they get all the blame.
In the military this is mitigated with the clear distinction between commissioned and non-commissioned officers. Not least because the isolation provides both support structures and necessary emotional distance (to a degree, of course). Being "elected" leader, especially with the pack dynamics of typical werewolf games is an extremely dubious honour that I'd flatly reject.
The fact that while you may be leader in character but not dominant over the player group makes things even stickier. You need to assert authority within the realm of the narrative without actually having that authority in reality. Again, something that will cause friction and resentment any way you cut it.
Depressing environments bleed emotions into play
The world of darkness does what it says on the tin. Having played in a horror game myself recently, the iconic themes of the world of darkness do not make for "happy" or, for that matter, validating game experiences in the main. (And, if they do, it's a violation of genre.) When you are faced with the stresses of being "leader" which are compounded by the stressors of the philosophies baked into the setting, no wonder you're having a rough time.
Some solutions:
On leadership:
Fundamentally, a gaming group is a relationship. Bad relationships that do not provide validation are a drain on mental and emotional resources. When they don't work, cut them off or change them. In your case, I'd play a game that's a bit lighter in tone and focus: a nice traditional dungeon crawl or similar heroic fantasy.
I'd also reject the leader role for all the reasons I outlined above. Or, if they force it upon you, demand the perquisites and authority that is concomitant with it: they can't have it both ways.
On the group:
I've found that group character creation creates a far more cohesive group. By having entangled backstories, the group can draw upon a deeper understanding of each others' characters, creating the basis for empathy and respect within the characters, instead of the necessary simulacrum imposed by players.
By articulating desired tropes, a "palette" (as Microscope) calls it, before the game begins, you'll be able to shape the narrative of the group in directions that you want to play. This allows you to avoid the nominally depressive tropes that come default with the setting (not limited to world of darkness) and describe a source for future characters to connect with the current group. Replacement characters, if they tie into the shared narrative, will continue to maintain the tropes and social trust.
Be practical:
As players, we shape our narratives to an amazing degree. Emulate Bron Hoddan in the Pirates of Ersatz. While playing, you will be aware of the desired practical outcome that will provide validation and satisfy your personal goals. With that outcome in mind, you then frame it in terms that suit both your character's narrative and the expected narratives of the other players such that they will act to reinforce your framing and thereby your outcome. If you fight their narrative control by "being a loner," it is difficult to achieve your own goals. If you help them work as a team and appear to sacrifice nobly on their behalf while executing your own goals... the entire process is smoother and more effective.
Note that I am not saying to lie. Instead, consider the causal constructions of your actions, the explanations for those actions to be an aspect of the role * separate* from the actions themselves. By manipulating the framing as well as the actions, you can provide the necessary hooks for the other players to support your version of reality, rather than rejecting it and, by extension, you.
Postscript
Looking at your comments to other questions, you should absolutely give this group two last tries. In the first trial (of one or two games), try a heroic romp where you can be "Big Damn Heroes." Require the players who need the spotlight be leader. In the second trial (again of one or two games), try a game where players can intrigue against each other (I'd recommend Ars Magica, but then again I recommend it for most things. Most games support PvP intrigue quite ably.) If neither game provides the validation you need and the spotlight the other players need, move on. Before you do anything, take a month break, sit down, relax, and try to game with some strangers. I'm pretty sure that if you go looking for games in the chat section of this site... someone will oblige. For more on the framing problem, I'd quite recommend Rule 34 by Stross, as it describes it in a delicious narrative context.
Best Answer
Crossdressing For Success
I play a character of a different gender than myself about 25% of the time judging from a review of my recent past characters. I think it's a great roleplaying challenge and is a lot of fun. Of course when I GM I run female characters all the time as a routine part of any game session, too.
"It's weird"
Though I've seen occasional forum trolls say that cross-gender RP is "weird," I have yet to meet anyone like that IRL and I've been gaming for 25 years. The majority of folks in the groups I've gamed with generally stick to characters of their own gender, but it's never been an issue for anyone when someone doesn't.
Since GMs have to play characters of another gender routinely, this tends to be an unsupportable premise anyway.
Let's look at the reasons that someone might be uncomfortable with someone else performing crossgender RP.
All you can do is feel out your group. I'm not sure how to mitigate any of these concerns without being completely condescending. "Don't worry Joe, this isn't all a dodge to get into your pants?" Frankly I'd just tell them to take a drama class and/or grow up if they're "uncomfortable" with the general idea.
"You're doing it wrong"
What I see a lot more commonly is complaints that "you are playing a man/woman wrong." As in, playing to a stereotype or otherwise in a way the complainant doesn't like.
Of course, the kind of game in which people criticize someone else's character - "you're not playing a dwarf right!" "You're not playing Lawful right!" tend to be reasonably immature, having not moved past a very simplistic view of the world. In my current group, I don't think anyone would have the ill grace to tell someone they aren't "playing their character right."
But perhaps you are doing it so bad as to break their immersion. That's pretty unlikely, as the challenges of RPing authentically are unlikely to hinge on so fine a detail, but reading the As a man, how can I roleplay a woman better? and As a girl, how can I roleplay a male character better? should help you to avoid anything too egregious.
Often times, complaints about authentic portrayals are specious - I know I'd get them a lot, even when I was specifically modeling my character's behavior on a specific incident from one of my female friends' lives! "A woman would never do X!" "Well, my friend Laura did that exact thing, so zip it."
Related are claims about how "sexist" you are playing the character. Frankly, you can do anything and it be interpreted as sexist (including not doing cross-gender RP) so as long as you're not clearly trying to be a punk you may as well ignore this.