"Wisely and slow. They stumble that run fast." -- William Shakespeare, Romeo and Juliet.
Don't seek or avoid exchanges without good reason. Exchanges are just moves, they make changes, and you must assess these changes. [It seems to me that many players exchange almost by reflex. I have a theory that when learning chess we may become anxious about leaving exchanges 'on', in case we leave the piece or pawn undefended later, and do not like the tension of unresolved exchange possibilities. A mark of maturity in a player is the capacity to manage tension in the position.]