But practice maintaining the more relaxed state for longer periods of time. Just keep at it. You'll begin to catch your tenseness sooner, to let the tension go, and to become more comfortably productive. You'll need reminders to help you remember to do many brief strategies. Otherwise you'll act out of habit with the old, too-tense reaction.
Reminders are important.
And make them fun. Your brief strategies during the day will work better if you spend time training more intensely at relaxing. In order to do well for a few seconds during a game. If so, play it for a while. Then sit quietly while maintaining that inner calm state.