I have come to the realization that Shaco is not, infact, a useless character. The problem is that his playstyle needs to be that middleground between Overly cautious and Extremely aggressive. Once you're caught that's it for you 9 times out of 10. Deceive is big cooldown but that doesn't mean that it doesn't do the job required.
For jungle, take shaco with the Machete x5 potions. at 42s put a Jitb at wolves. Place 2-3 more (Depending on your cdr) directly behind where the blue buff will spawn, if it isn't just right you will end up killing the little minions and ruin your jungle entirely.
Minions have spawned. 1:40 the wolves spawn. Your JitB will do some initial aggro, but try to work your way around to the back of the big wolf to get your passive off. You WILL need help to get them down before blue spawns. Kill blue, Preferably without having to use smite (Do not get help from singed poisons, Darius' passive, or teemo with E.) once done, rush to red and put down 2 boxes just outside of the actual camp. Aggro the red into them and get behind. Smite. gank. Win forever.
armor/magic pen marks, AD or gp10 seals, Armor glyphs, and armor/magic pen quints.
I prefer to take the gp10 seals in case farming goes south or not a lot of gank opportunities.
Masteries are a standard 21 offense, with all the armor pen, and then 9 into support. For the 9th point I either take the 0.5gp10 or the buff duration (depending on team comp/runes I have in place already.) The gold-per may not make a huge difference, but every penny counts!
Items-wise is very simple.
Machete / potionx5 ===> Boots 1 (Build into zerk boots) ===> core item; Either Black Cleaver or BotRK.
I suggest getting both black cleaver and BotRK for the added effects it gives to your clone.
If the enemy team has a lot of cc, consider swapping out cleaver for something like Mercurial Scimitar. No sense dieing to something stupid or getting caught to long with your pants down.
Teamfights is simple. Either slow an enemy with a teammate and WALK into the fight, do NOT waste your Q, and proceed to do your damage. If more enemies comes in you must gauge if it is wise to fight or flee. Lots of cc? deceive out and wait for the CC to start, or bait with scimitar. Hit R as early as possible to get the most out of that little bastard. (I like to use q and then R, because it removes any pings you have on you beforehand.)
Cleanup, pick on the SQUISHY champs only, and slow runners.