I hate playing top, but I manage. What I do is go someone with escape skill/cc and have tp. Even if top is getting frustrating, being able to tp bot and get a bot advantage is a HUGE lead. Especially since dragon is there as well. Other than that, there's what you stated. Grab 2 green wards on your first back and place one in between mid and top and another closer to you. There's roaming too, but if you're against someone that snowballs hard off of farming, it can either go good or bad. I know freezing your lane sucks if you like to play aggressive, but if you wait and only hit the minions on the last hit, it makes it easier for your jungler to gank for you and you shouldn't have a huge disadvantage on farm. After all, 16 cs is equivalent to one kill!
Said all that.... farm, ward, know when to engage and disengage, save tp to get your allies fed. This is probably meh advice, but I try! :D