One of the things that will help your training is to think positive thoughts all the time.
The words we pick to say or think matter.
EX: Just the other day while training a veteran client as she was reaching a deep level of muscle fatigue I said: "Don't quit, don't quit!"
And lo and behold...she quit.
I said "How come you just stopped? You were about to finish that last rep and call upon those last few straggling fast twitch fibers!"
She replied: "You said to quit."
She's right - I did.
Instead I should have said: "Keep at it, keep at it!" or "Squeeze those shoulders stronger." or something akin to this.
If you have a training partner or if you train yourself, always use a positive, active prose so that your semi-subconscious gets the correct message.
Say "Breathe" not "Don't hold your breath."
Say "Shoulders down" not "Don't shrug your shoulders"
You get the picture. Very The Secret-ish and very effective!