I feel like I'm never in control of doubles, at all. I feel like I can't really make significant changes to my approach to a game of doubles in order to win.
Despite that, I've got a surprisingly strong record. The key for me is that I pick up whichever role my partner prefers NOT to play.
Until a certain level, doubles simply consists of a) putting the ball back on the table and b) playing positive attacking shots against weaker balls. If my partner isn't keen on b) then I'll take that role - I'll go all-out attack on both sides (unless I'm out of position, in which case see a). However, if my partner is a strong attacking player, I'll just keep putting the ball on and making it difficult for opponents to attack us, and let my partner do the bulk of the work.
The other key is communication. Soooo many of my partners aren't ready for pop-ups off my serves/pimps. If my opponents are giving us those easy balls and my partner isn't ready for it, I'll explain when to be ready - "I'm serving topspin/float here, stay close and get ready to attack" or "when I push off my red, if opponents push back, it'll come high - be ready for it". After time - perhaps not in the same match, perhaps in the next match or the following - they'll start to subconsciously know when to expect pop-ups and when to expect heavy backspin from opponents pushing my chops.
Finally, a pretty basic one - if you can't catch your opponents out with serves, work hard on perfecting a simple backhand (righty players) short backspin serve. Doesn't have to be the best serve in the world, just make sure it can't be lashed past you/your partner. There's nothing more frustrating in doubles than watching your partner serve light, mid-length, mid-height topspin especially when the ball comes flying past you and people look at you as if you should've been able to do something with it...
