Backstab is most effective after using Deceive. A guaranteed critical strike with a bonus 20% damage (not a true critical), then quickly followed by a 120% damage Two-Shiv PoisonTwo-Shiv Poison will deal a reasonable amount of damage to any champion's health.
Deceive can be used to go through walls in a similar way to the summoner spell Flash, so it can help you make a clean escape.
Unlike 图奇的Ambush, Deceive allows Shaco to enter stealth right away but it has a shorter duration.
Warding the Jungle and surrounding area with Jack In The BoxJack In The Box can allow Shaco to see a gank coming and escape before the other team initiates. Placing them in the brush will prevent enemies from hiding there.
The Hallucinate clone can be, like most secondary units, controlled by pressing Alt + doing the order with right-click. It does not use any abilities or activated items, however. Use it to push turrets or farm minion waves once the duel/teamfight is over.
Sometimes Shaco is best played tactically. Start off with a point in Jack In The BoxJack In The Box. If you can, sneak into your lane without being seen by enemies and get to your bush. When in your bush have your lane partner keep the enemies away from the bush. Once you've placed a lot of Jack In The BoxJack In The Box walk out of the bush and bait your enemies into a bush. Between levels 1-4 this should be an easy kill.
Keep in mind that experienced players will be wary of Jack In The BoxJack In The Box in bushes, so this will probably not work. A better tactic may be to plant them in an enemy's jungle or just strictly as wards, or to place them near your turret to make defending easier.
Shaco has a number of differences from his clone that reduce its effectiveness against observant players. He can be distinguished from his clone in the following ways: his clone never shows a neutral buff graphic, pinging Shaco before he uses Hallucinatewill cause the ping to follow the real Shaco, and the clone wont have any items so if you click him you'll know if its the real one or not, at last if he Hallucinate with Trinity Force, Lich Bane or Sheen you are able to tell which one is the real according to yellow/red glow.
Oracle's Elixir isn't too effective at countering Shaco's stealth if he is trying to escape. The stealth only lasts a few seconds and gives him the ability to flash over walls. It still, however, counters a Shaco stealthing for offense. it also helps you snipe or stay away from Jack In The BoxJack In The Box.
When laning, having a teammate with Teleport can be very useful. Placing a Jack In The BoxJack In The Box in a bush and having a teammate teleport to it can provide a fantastic surprise attack that the other team wouldn't be able to call MIA quickly enough. Having a mid-laner do this can be even more advantageous due to the level difference.
Shaco is often a prime target in team fights. You should be using this to your advantage. Coming in behind the enemies and posing yourself as a threat will cause them to attack you. When they start to turn to you, use your Jack In The BoxJack In The Box to fear or provide another target. You can Deceive once they start to pursue you, and while you deceive send in your clone for additional distraction. All this will allow your team to attack with less counter attack since enemies will be focusing on you.
A Banshee's Veil will help you do this by resisting a stun or silence and allow you to Deceive out safely.
If your team is defending a turret from attack, Shaco can push another lane (split-pushing). Shaco's team should be able 4-man defend a turret because of the offensive capability of the turret filling in for Shaco, and an AD Shaco can take turrets down very quickly with his Hallucinate. If the enemy team sends a few champions to defend the turret and chase you down, your team would have an advantage in attacking the others. If the entire team decides to target you, that leaves their other turrets open for attack by your team.