Caitlyn main here, but I'm pre 30 (I tend to play with lots of 30s so I like to think I'm better than average for my rank, but anyway...) so know that when you read this.

-Try to move unpredictably. It'll make it harder for cait to hit Qs. -Watch where you walk. Traps in bushes can be difficult to see if you're not paying close attention. -Remember that her traps give a split second of vision. If she traps a bush you're in, she saw you. -Try to keep track of which bushes are warded. Taking full damage from a Q because you sat in a bush instead of taking reduced damage from being behind minions is bad. -Cait /will/ have a longer auto range than you. Either come closer and try to trade if you like, or stay out of her range, but don't be in the area where she can poke you with autos but you can't poke back. -If you can silence her for a bit, she can't net away which will let you get some damage in. Also, try to force her to net a lot to use up mana. -Once she hits 6, BE CAREFUL. Make sure your support (or adc depending on who you are) is nearby you to intercept bullet from ult if necessary. That first free kill as they leave lane using cait's ult is important, deny it or at least make it less free.

I believe the best time to deal with Cait is midgame. She's good early and late, but relatively weak midgame. If you can out scale her there, that's good. I'm not so sure about this last piece of advice here, I'm not quite sure about how good my grasp of overall strategy is...

I hope this helped at least a bit, the mechanical tips were pretty obvious I think and there was basically nothing besides that :P . Oh well. Sorry about that...