Remember, practice makes perfect, unless you're playing 'Stairway to Heaven' for the 12th time in a row. In that case, you're just a hero.
Acknowledge the inevitable guitar solo and accept that it's going to take 17 takes to get it right.
Procrastination Hack Tip: If you find yourself stuck on a solo, just play it with your eyes closed and a confident smirk. No one will notice (except your neighbor, who will probably call the police).