I am playing double. Entry level, played for 6 months. Just want to get some basic training to master some basic tricks in a professional way.
Don't go for tricks... it's fun, but they have a low success rate, even when your good at it.
The basics
1. Service (at the end when everybody is quitting, take a court and practice your service for 5-10 min., near the net and in the inner 1 square foot box, then far side and on the back, all with the same motion) A good service will be difficult to attack and will put your team in a better position for the next shot.
2. Learn how to move on the court. From a central position, you should be able to access any point in the court in 2 steps or less. You can find tutorials on youtube.
3. Position, there's a few position patterns to learn for double and when the 2 players are playing the same positions pattern, you are one step ahead in the game. You can find tutorials on youtube.
4. Hitting techniques, how to hold the racket, forehand, backhand, smash, ect. Obviously a coach is a nice choice here, but you can ask a more advance player to help you with it. Personnally, I'm more incline to help toward the end of the night. And I will help anybody that is willing to work.
Good luck finding a coach!