When it comes to rhythm guitar, i can hold my own pretty well. Im comfortable writing my own songs now, and can come up with half-decent riffs. The area i do struggle with, however, is soloing. I know that to become a good lead guitarist, you must develop a mental library of licks, which you can utilize and play when needed. So, as you do, Im attempting to develop this library with as many different licks as i can.
My question is, should I learn one Lick for hours on end, pursuing to perfect it, or should I try and learn a variety of riffs in the same session?
The way I see it, playing the same thing over and over again can and will get tedious. However, surely after hours of practicing, and building up speed, youll have it learnt and can play it off by heart, right?
However, if you were to learn a variety of licks at the same time, working on speeding all of them up, wouldnt you learn more riffs in less time? I seem to learn riffs, and then forget them a few days later, and I know I must be doing something wrong, if I cant retain all these different techniques.

So how SHOULD i be learning licks? One at a time, or a variety at once? Would the correct method allow me to remember these licks too?

Thanks for all your help guys, in advance
It really depends. Some people like taking things one by one, some do multiple at once. I think the important thing to remember though is that if your learning multiple things, you are not necessarily learning more riffs in less time. It's about quality and not quantity, you know the riffs when you do, you shouldn't really be worrying about "oh man i got to learn this in x amount of time", you should be making sure you get it down.

I think a important tool in remembering phrases is to sing them and analyze what chord they are being played over. For example i am currently working on a couple of phrases, one being from a charlie parker tune. Now what i do is that i:

1) Practice playing the lick on the guitar, so i got all the muscle memory down and can actually play it.
2) Practice playing and singing the lick at the same time, so i that i get it more into my head.
3) Playing the chord(s) it is played over and sing it.
4) Repeat in all keys.

This way i can remember phrases and modify them on the spot if i feel like it, it sharpens my ear and improves my improvisation.

I think it's better to think of phrases as sounds rather than patterns on the guitar you play. You want to relate to everything as purely and musically as possible.
Fusion and jazz musician, a fan of most music.

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