Focus on the present moment. Stay in the moment.
You can get better, or you can get all gooey, and crotchety, old, pathetic, icky, gross. Not me. Not into it.
Turn off your mind, and focus on what you've got to do - task at hand.
I can do things at 45, not because I can do a bunch of pull-ups, it's because I do Yoga!
Falling and getting back up is what brings you success.
Do NOT say you “can’t”! You can say, “I don’t want to”. You can say, “I’m not willing to put forth the effort”. But DO NOT say you CAN’T!