TL;DR: I'm looking for a technique for handing out XP during sessions that is both rewarding for the players and easy to handle as the GM. Doesn't have to be RAW; personal experience is welcome.
I GM a roleplay heavy homebrewed 5e campaign for two players. We've been fudging the rules left and right to make it more fun for us as a group, but I've hit a wall when it comes to XP.
My players really like the idea of getting XP on a per-encounter basis (whether this is combat-only or (more likely) from roleplay as well) because they like the constant "praise" and the sense of accomplishment. They also seem to take a sort of glee out of writing down the incredibly stupid reasons they got XP so they can go back and laugh about encounters later. If it was something I was fluent in I would love to similarly give them laughably small amounts of XP for things I thought were in-character, funny, or creative (kind of like inspiration, but as XP).
The problem is that the mechanics of the system they want are overwhelming for me. I tend to make things up on the fly (both roleplay and combat encounters) and therefore haven't planned ahead and have no idea how much XP any one section of play should be worth. I also just tend to forget. A lot. Like literally every single time they probably should get XP it's so far from my mind that I often don't remember XP is a thing until half a week after the session when I get a d'oh moment. I'm new to GMing and handing out XP is not a simple thing for me; calculating the correct amounts takes me time to not mess up.
I tried remembering to keep a rough tally during play and hand them a "session" XP tally at the end of each game, but I tend to either forget to tally bits, or be so wiped by all the fun we had that I don't have it in me to do the math post-session.
My preferred solution would be to just have them level up when it makes sense for our narrative, like at the end of each story arc, or after a certain amount of time had passed in-game. This doesn't give them the feedback they're looking for however, which I appreciate and am therefore looking for ways to resolve.
Does anyone have similar experience with XP in their games? How did you handle parceling it out?
Best Answer
Use a mixed system: Chunks of XP at milestones...
It's funny: your situation sounds 90% identical to what I've been struggling with for a while, especially the part about forgetting to give out XP for long stretches.
Personally, I've switched primarily to a milestone system: every time the PCs hit an important milestone or made some progress, I dole out a precalculated amount of XP (or even just an entire level at a time). It seems to me that such a system would work for you. Instead of calculating XP, you should break up a level gain into smaller chunks, and go with that.
You say that you make things up on the fly, but such a progression method isn't too difficult to do either--you could split a level-up into smaller chunks, say 1/4 or 1/2 of a level, and dole those out accordingly. You're effectively reducing the XP system from numbers in the thousands to much smaller numbers, but it really reduces the mental overhead for the system. You're not going to get a preparation-free method for dealing with this issue, in my opinion, but this approach should help.
For example, if the players decide to detour into a sidequest, you can simply decide that the sidequest is worth half a level. If the PCs finish a dungeon, that might be worth a full level.
...and bits of XP for fun
At the same time, you can still use small amounts of XP as rewards. When the XP system uses numbers in the tens of thousands, you can hand out 5, 10, or even 100 XP out freely without worrying about unbalancing level-ups, especially if you're using the chunked level progression described above. I've played in games where the DM does this, and it has zero functional effect on the game, except when players like to brag that they're actually 200 xp ahead of others (which is the intended situation, right?).
Incidentally, this also solves a similar problem I had with rapid leveling--I like to throw difficult encounters at my players, but the XP gains were so high that they'd advance far too quickly for my taste. Leveling up by milestones completely eliminates this problem too, and gives you a lot more flexibility in how you run your game.