Most musicians spend the majority of there prep time getting ready for the show, not fixing things afterward. I used to be the same way, until a friend suggested I start using performances as an evaluation instead of a final grade. Here’s what I mean, and how to apply it to your routine: 

1. Make a recording during the show.

I recommend you take a video recording of your playing, and go back over it when you’re home. What did you do right? What are the areas you can improve on? 

2. Make a list.

Write down a list of the things you can improve. Be critical, and look for specifics as well as general tendencies in your playing. I found out after doing this a few times that I used a particular lick before every country chorus. I practiced a number of other licks in practice to compensate, and the problem disappeared. 

3. Prioritize in practice. 

Make sure to dedicate specific time during the week to practice just what you screwed up on at the gig. Addressing the problem in practice at home will do wonders for your performance next time you hit the stage. 

4. Ask a band member you trust.

We’re often blind to our own faults, while band mates may be painfully aware of them. Ask a bandmate that you trust and respect for honest feedback, and tell him to not hold any punches. Your ego may be bruised, but you’ll know the truth.