Almost every amateur I observe on the golf course has several swing thoughts, including a backswing thought, on every shot. Almost none of them have a consistent pre-shot routine, even though every time they watch pros playing on T.V., every pro goes through his or her pre-shot routine every time.
Meanwhile back at playing. When you play, play. When you practice, practice. You can practice on the golf course (I don’t mean hitting extra balls) as long as you don’t care about your score. In fact, the golf course is a great place to practice shots – not a good place to work on your swing. The practice tee is a better place for that. Most people feel they don’t have much or enough time to practice. Well guess what? If you don’t practice at least a little bit, once in a while, your game isn’t likely to improve. The most effective way to multiply exponentially the positive effects of practice (even if it’s only ten minutes in the backyard with sponge golf balls (yes they make them) is to get visual feed back on what you are doing. Lots of people have video cameras with small viewing screens on them. Set up the camera when you practice. If you don’t have a tripod, use a table or chair. Most people are amazed at how much difference there is between what they are doing and what they think they are doing. You are going to learn whatever you practice so make sure you are practicing what you think you are practicing.