Its all about the box placement.
Shaco wants the enemy to run into his boxes, which is why he is a good support at the moment due to the amount of engage supports being played.
In lane:
Try to keep your boxes in the middle of the lane where your carry will be standing. Most shaco supports I see always put it at the edge of lane, meaning most of the boxes just time out.
If the enemy have sweepers and control wards around lane and keep destroying your boxes, head into enemy jungle to be a pest there.
Its also usually worth having a box at dragon to delay the enemy if they start it.
E is surprisingly good at poke. Try to use it whenever comet is up.
You can cheese the enemy buff at level 1 using your boxes if you get there in time.
Most of lane shaco is just anticipating what the enemy will do.
Out of lane:
Very few mechanics needed past Q and abusing ult to dodge abilities.
If an ally is split pushing, setup boxes around their jungle side and go be a threat with your team on the other. You can completely block of paths with boxes and give the pusher plenty of time to escape.
Enemies run. Boxes dont. You gotta. E behind enemies to place your boxes in a skirmish.
Ult to take towers and objectives.
Keep boxes at the entrances to both pits.
Try to work out where fights will happen and make sure that area is covered in 3+ boxes.
Coming from 100k points of AP shaco top. I feel these things will stay similar on the opposite side of the map.
As Chalangar said, you cant just "pick up shaco and win". Shaco is probably one of the champions that require the most game knowledge. Pink Ward wins because he knows **exactly **what the enemy is going to do.