Well, this has probably been said by many, many writers, but still: Just keep writing! And keep reading. Read some really fine authors, whose works you enjoy. And as you go along, ask yourself "how did she do that?" or "how did he pull me into that scene?" You'll find that you can usually reconstruct just what techniques worked to create an emotion or build a scene. By seeing what works, you can learn to create the same effect.
Another things is: watch people, see how they move and think how you might describe it. Listen to people talking, and try to reconstruct chance conversations later, complete with facial expressions. Try this out with friends and family and let them read the recap. Did you capture the nuances, the emotions? Did you miss something important? This sort of exercise can be very helpful later on when you need to write dialog. And believe me, even if you write nothing cookbooks, you'll still need to write dialog!