I think the Only way to do it is to keep thinking about it and reminding yourself to stop. ralph bowen told me at a jazz camp that I was at that he tries to minimize all movement in his body other then his fingers when he plays, because excess movement leads to tension and gets in the way of playing the horn. that's why he's like a statue when he plays. try practicing longtones with your fingers as light on the keys as possible, and then scales. start slow and get faster and keep concentrating on having your arms, shoulders, wrists, and of course fingers relaxed. I've been where you are before, man! you can do it!