Miss Fortune Build
Not Updated For Current Season
Early Game: I start in mid with boots of speed, 2 health pots, and one mana pot. With one point in Double Up, Miss Fortune's range is quite substantial always aim for a creep in line with an enemy champion and you should be able to harass with greater range than almost any enemy champion, as your second ability get Make It Rain, and shower on clustered creep. MAKE SURE TO LAST HIT CREEP AS MUCH AS POSSIBLE.
Mid Game: As you've completed your boots and started or finished Phantom Dancer I recommend buying the health crystal used to make Frozen Mallet as Miss Fortune's survivability is horrible unless you stack some health. Try to engage in team fight with a Double Up-Make it Rain-Bullet Time combo, get ganks and try not to be by yourself when more than 2 enemies are missing.
Late Game: After you've completed Phantom Dancer, Frozen Mallet and Berzerker's boots, There are 3 very good items to choose from depending on the make up of the enemy team, Madred's Bloodrazer, Infinity Edge, and Last Whisper. I usually build Last Whisper First as it's attack speed/ armor pen helps tremendously after that I go Infinity Edge unless I'm taking a lot of damage or then enemies are health stackers in which case I go Madreds.
This is my first build and I have a hard time describing exactly what I'm trying to put out there, so any suggestions/comments feel free, Thank you.
Also, with this champion I've had a 15 game winning streak where in every single game I was the game changer, my best scores where 28/3/10, and 25/5/8, but I had many great games with her.