My habit is to wind my manual wind watches at essentially the same time each day. It is best as well to maintain at least the power at half full, i.e. don't let the watch run down completely before rewinding. Your watch will run more accurately and consistently, if kept at least half wound or more on a consistent basis. This mitigates an issue called isosynchronism, which you can look up in the archives.
Of course, you can let the watch run until it stops. It won't hurt the movement, but for accuracy and consistency keep it wound most of the time.