Well if you are really affraid of being hooked versus Pudge, having wards high ground is the best solution.
You can ask your support to put up wards so you will always see where pudge is (see screenshot at the end).
Then as an Invoker you can put an early point in wex just fot ghost walking away. This might delay your dual forge spirit (in the QE built) but if you really feel insecure that might be the best way to go.
With any mid hero you have to not make the basic mistake versus pudge which is : try to escape the rot by running. If you ever get hooked, trade hit with pudge and burst him with your spell. If you try to run you're almost certainly dead. Pudge has a really low armor at low level so your right click damage will hurt him badly, plus remember that the rot inflict damage to himself too so you can often turn a hook into a kill for yourself, just dont be afraid to manfight him. Pudge players tend to get overconfident when they land a hook, prove them they should not.
Another great tip is : rot does not dispell healing salve until its level 4, so you can use a salve to get some hp back between 2 hit and that might save your life.
Screenshots
Those wards' position can be used to avoid any kind of early ganks. You can watch the minimap to have an idea on what vision it gives.
When you are on the Radiant side :
When you are on the Dire side :
This last observer is usefull to scout mid highgrounds at all time to avoid hooks (you can place it on both side but preferably the enemy's side) :
Best Answer
When you stand in front of a creep he will try to pass on your left/right side,so you need to adequately move slightly left/right to block him from passing around you.As long as you keep blocking the first creep on the head of the wave,the creeps that follow will block each other.And avoid scattering the wave(with spells,other heroes,courier...) since creeps that are further away from group will have different pathfinding and could pass you from weird directions.
It is best to start blocking near your Tier 2 tower,since at that point your creeps will be nicely lined up.
If you have another teammate in the lane it is best that one blocks the creeps and other one stays further in front of the group.So if a creep bypasses you,your teammate will be there ready to block him,while you go ahead in case creep passes him too.
Blocking gets easier with larger heroes(pudge,lucifer...) since you have to maneuver less,and if hero is slower you will less likely move too far on the sides which could make the creep pass by you and ruin the block.
Pulling you can attack the neutral creeps(side lanes) and lead them close to your creeps on lane making them fight behind your tower and delaying the creeps progress.
Since patch 6.79 creeps in the safe lane have a bonus movement speed for few seconds when they initially spawn,making them harder to block.Watch for more details.
Hero Skills (this is prohibited by some tournament rules)
Earthshaker can use "fissure" on certain places and completely block the creeps from progressing(for the duration).
Furion can use "sprout" to trap the creeps(if you manage to group them enough).
Clockwerk can use "cogs" to trap the creeps(if you manage to group them enough).
Videos