All you need to know is that until lv6, you are nothing serious. It is the time to nit pick at your enemy's health or farm. You're too squishy to engage in direct combat before then. After you his lv six, you should have enough money to recall and pick up the hextech revolver. Afterwards teleport back to your turret, and let the mayhem begin.

In situations as such, I wait until my teleport is cooled down, and I place a ward in a bush near the enemy turret. After, I run off to bot lane for a moment to get fed off of the enemy adc. The enemy mid or top laner will want to take advantage of your absence. That's when you teleport onto your ward and catch him/her off guard. Now you have a minimum of two kills, leading to Akali OP.

Forget lanes even exist at this point. Go crazy on any enemy you know you can take. If you're on top, move to mid and assassinate the enemy. If you're on mid, move to top. At any point, when the enemy begins to push your lane again, teleport back to the turret, and finish him/her.

You should have a minimum of ten kills. With that said, feel free to jump into team fights, even if you're outnumbered. Unless an enemy has a stun, you can usually take them. Do not be shy. Enemy's a food for the master assassin

Do not fear sneaking inhibs. With my masteries, they'll crumble in a matter of max ten seconds. If the enemy tries to stop you, throw a smoke bomb, time it correctly, and take them down one at a time. The last one or two will usually try to flee. It's your choice on whether or not you want to show mercy.