In the jungle you should start with a machet and two pots. You can do 2 things. you start with e always.
1st tactic: you put down your 1st bow at 1:00 at red (if the enemy jungler starts with blue) and put more boxes as fast as you can. Kill the red (without using smite), put 1 on your q, go to the enemy blue. If the enemy jungler is there, you are lucky, and you probably can kill him/her. If he/she is not there, take the buff, you'll probably can, Then go on killing jungle mobs and ganking.
2nd tactic: start same, but you put down 2 boxes at the stones, then one in front of the red, then one to stones again. You start kill the stones (don't smite them!), then make the red walk into your box, and so going on.

-Try to backstab everybody and everything. When you take buffs, put down your box, then try to backstab. It will deal more damage, because of your passive.
-Try to gank without the enemy laner knows, that you're already on the lane. Start the gank with jumping in with your q, then you can do 2 things:
-put down a box on the way where he/she can escape, then attack
-just attack (you can do this, when the enemy is on low hp)
whatever you do, you can deal tons of damage, and gank early (like right after red, then won't expect it)
-In teamfights try to keep safe, because you're squishy, and you can die with ease. Q into the fight, kill some people, go away, like nothing happened.

After you got home first time, you should have enought money to buy at least a stalker's blade without upgrade, but if you have some money left, you can buy long sword or boots of speed or maybe a tiamat. Then keep on ganking, getting kills, getting gold. Buy the Stalker's blade - warrior, then Berserker's greaves - homeguard. After go on killing, buy Hydra, then the other suggested items.

strengths:

-easy camp clearing
-stealth
-awesome scaling damage
-you can have 2 shacos and the same time (ultimate)

weaknesses:

-squishy (you can escape by using your q smartly)
-Jack in the box and Hallucinate damages only from AP, and Two-shiv poison deals for about 50% of your AD