What do you do when you have a ton of new songs and solos to learn and you have to play a gig in a couple of weeks?

Here's a process that works:

1. Come up with a simple and easy way of playing the songs and solos that you find challenging. Focus on coming up with the easiest way of playing the chords and solos. Nobody will think "Oh he can't play the real thing" instead they will just see a musician playing the song his own way. 

Come up with stuff that is as close to the original as possible to satisfy the band members, but then use something you can play really well. When you have established that easy foundation you have something to fall back on. A secure base that will get you through the gig perfectly. This will make you confident and calmer when you play.

Then play through the list of songs and stay with each song until you can remember everything and it gets a little boring. You might find that some of the songs you need to play 10 or twenty times (Or more) but that's what it takes. 

Do not rush to the next song before you really feel you have the present song completely under control. It should be easy, easy, easy before you move on.

Then go on to the next song and give that your total focus. Then when you come full circle you start over again and do the same thing. Now you will have forgotten some of the first song but then you practice it again until it's absolutely effortless for you to play it. DO NOT RUSH IT. Stay with the song you working on until it's easy easy easy.

Throughout this process you play the easy version of everything. Do not get overambitious but focus instead on learning the easiest version first to establish a maximum level of confidence in yourself that you can get through the gig easily. 

The more relaxed and confident you are the greater the chance that you are going to take chances and go for the more advanced stuff in the actual playing situation.

When you master the easy version of each song completely you can use the remaining time to go for the harder parts. But focus on one solo at a time and make sure that solo is easy to play before you move on to the next song. 

Do not practice a little on one solo, then move on to the next, aso. That is a reciepe for failure. Don't try to play a bunch of solos that you're not comfortable with on stage. Instead make sure that you really know what you're doing so you can have the most fun in the playing situation. 

You don't have time to be ambitious here. you can be ambitious in your regular practicing rutine, but not when
you have 40 songs to learn and a deadline.

If your mind is racing to build an amazingly impressive performance by wanting to master a lot of new stuff in the practice time you have before the gig, stop it. It is not the time for this. 

Instead focus on creating an amazing experience for yourself by focusing on mastering the easiest version of everything and then use any spare time you have to focus on mastering the harder parts. But work from a foundation of security.

So to recap:

Practice playing everything the easiest version possible first. And do not go on to practicing the harder stuff before you can play all the songs in the easy version perfectly and confidently.

Play through each song over and over again until you master it completely - Do not move on to the next before you are there.

Then when you come full circle, start over again and do the same thing. Now you will have forgotten parts of what you practiced days or hours ago. Re-practice each song until you master it completely. Keep doing this until you haven't forgotten a thing when you start over.

Then spend the remaining time focusing on learning the harder parts.

Focus on creating a great playing experience for yourself on stage and forget about impressing people. In the end this is the most effective way of making sure that you will impress people the most (Ironically enough)