I can show you some stuff. I don't main him anymore but I still play him from time to time. Don't go by my match history, I was trying out some ap shaco support (not as bad as it sounds, not as good as other things)
General tips
Drop boxes in choke points all the time, even if it doesn't seem useful it may come in handy later. ALWAYS have a box somewhere you can run to for escapes.
If you q in and then ult, the clone becomes visible while you remain invisible, this tricks many people into thinking the clone is you appearing from stealth. (very important if you build ap, as clone can do 1k dmg easily).
Clone is OP for juking, go into a bush, ult, run into them and stop (with the s key) but make the clone run away, or have you split up in two different directions.
If you play a lot, you can actually dodge things by ulting at the PERFECT time. (jinx ult, karthus ult, random shit)
Sometimes it's better to just run in as shaco, place a box, and then when they try to escape q after them. (during ganks)
Save your e when ganking as it adds a slow to your auto when not on CD, and it does bonus dmg if it hits from behind.