Now, I don't know what kind of setup you have. I use my computer for everything, thus rendering it my very life and if anything happens to it I'm gonna **** my soul right out and keel over. That being said, I have a user friendly setup. I record my rhythm and listen to it with headphones, kinda getting an idea of what I think would sound good with it. Then I plug my guitar into my computer and play the track while doing some lead work over it, seeing how my ideas work and so forth. Let me also stress this. When you get something, embed it in your brain. I've only made one song that has leads and I can't remember anything more than a few key parts. Gimme a break though, it was about 2 minutes and 20 seconds of soloing and I've only made one song with solos. I can remember it if I put the time into working with it as it wasn't really much of an expedition with notes (but it still sounds good). So, work with it, you can forget solos so much easier than you can a catchy riff. Start small, don't drown yourself with too long of solos. Also, I might add I hit record at one point and literally made things up as I went along for about 4 minutes and I can't remember a single note of that. Practice them. Learn scales and an array of licks and tricks you can do to spice them up. It'll come easy once you get the ball rolling, just put the time where needed.