Time trouble


Taking a long time to think is not a bad thing, I would suggest sticking with longer time controls. Blitz is bad for the brain, which I can attest to as a blitz addict....

When you feel like thinking, play longer chess. (e.g at least 30 mins) but for intuition, play blitz.
No one has enough time to think a lot in blitz, so go off your instincts in a position, try to make sure you don't drop pieces, stuff like that.
Long games are better for calculation. You get to sit back and really analyse the position. There is a bit of analysis in blitz, but it's only at certain critical points.
You should have at least three moves in your mind for both variants though.
Hope this helped!

Try to think ahead on your opponent's time.
When your opponent is thinking, don't just sit there and wait for their move. Instead, try to predict their best move (and in turn, think of your response). If you're able to, try to predict several of your opponent's best moves, and your respective responses.
Granted, sometimes they'll catch you by surprise, and you'll have to sit there and figure out what to do next. Most of the time, though, by thinking ahead, you'll have an idea of what you want to do right away (or at least quicker than normal).
Plus: practice!