Here are some Basics:
Press F on constructions sites to change them, but you have to change it at least once before picking what you are building or else it'll create something random. (Clarification: Don't throw a site down and immediately start building whatever its first set with, you have to change it.)
Most equipment have a variety of places that you can switch, move, turn, or pull back. Build each thing and walk around playing with it.
Use mental physics to determine catapult shots, once again something you have to play around with it to get a good feel. It has a block that determines how quickly or late the rock is released, it has a draw back that determines how hard it's being lobbed and lastly it has options to move, turn, or put on the brakes.
Always start off with an equipment box, you need easy access to c-materials especially in strat. (There is a global 5 box max and thus there is an unwritten rule to distribute it based on the 2|3 rule, with whoever getting the third being the winner.)
Ladders:
The direction you face when throwing a ladder makes it fall in that direction and it'll first appear at a near perfect vertical angle. Another type of skill that requires practice and having a good eye.
Create beautiful ladder art.
Go to a duel server and hide in the corner of the map, bring a friend if you need one to make it go quicker. You are protected there and if someone messes with you, post a ban thread.