First time i played this champion i fell in love with it. It is just so much fun to play, what i did was that i went to op.gg and mobafire and search for a good build it seemed that most people are playing this champion as an assassin. even the ones who build Trinity Force. so i played that way, but it was never as effective as a real assasin like Kha'Zix. because it lacks that initial burst of damage that those champions have. Anyway it didn't really work for me. because the jg clear was very slow and between buying Tiamat, Duskblade of Draktharr. you will never get out of your jg, because your build is too expensive. and if you get out without proper burst you will not be effective. But this champion have a lot of potential and you can do so many builds with it. You just have to figure out your play style. the Jack In The Box is such a great ability you can do so many out play scenarios with it.
As for this build, I felt like Shaco doesn't have that Assassin burst. you still play like an assassin but a bruiser assassin. and you need a proper bruiser keystone, electocute is not it. and the build should have synergy with items. and if you are bruiser you should be a little tanky as well a lot can happen until you kill your target.

Best way to start the game is going straight to your Blue buff and drop Jack In The Box you keep spamming Jack In The Box] at the buff location. that way you wouldn't need leash. the Jack In The Box will kill blue buff easy. then you go gromp, wolfs, scuttle crab and then red. you really want to take scuttle crab you will need as much gold as you can get. Tiamat is a must and it is expensive. I will not use Smite before red buff. you might have to Smite big raptor or big krug. I wouldn't force a gank if not necessary in first clear. unless the enemy is overstepping their boundaries or they are very killable you don't have to gank. of course it is very situational.

early game you need to upgrade your Deceive as much as you can, so you can situate yourself in a good position behind enemy. and place a Jack In The Box so they run to it. and then go to the other side and Two-Shiv Poison to slow. the enemy will panic and runs to the Jack In The Box. you always want to stab your enemy in the back because of your passive. Backstab, it has a very low CD and it will assure a good damage output. beside its a great way to kite enemies that can't hit you behind them.