So you want to play Caitlyn very smart. You use exhaust three different ways, Either to escape, chase, kill. When I say kill I mean you pop exhaust and you fire everything you got at enemy champion. I have gotten many early game kills this way.

When ever possible you want to make sure you are solo lane. This helps Caitlyn out a lot. On top of that she is very effective against almost any champion she is solo lanning against.

Mid game if you team has been doing good. Is when Caitlyn really starts to shine. I know most people say shes early game and thens she blah. Well so far with this Caitlyn build ive been doing good the whole game. You want to spam Q as much as possible, watching your manna of course. You will get manna deprived so watch closely. When exhausted is used place traps in front of Champion you are attacking. Then spamming your attack and Q. Normally it wont come to having to use your ulti.

By late game you should have up to your phantom dancers and should have enough damage and attack speed that you are actually starting team fights. Using E to run when needed. But by now you have almost all of your gear and hopefully your team is decent so it wont rely on you to much.

Also for your last item, its very situational. One game i went Guardians Angel, another i went Banshees Veil, and of course another i went Bloodthrister.

Just make sure to spam Q and place traps when ever possible to catch a fleeing or chasing Champion. And your normal attack should do the rest.

Here our a few games I have had with this Build. Both games took about 15 to 20 min. One destroyed their nexus and the other they surrendered.