Just Jam with some people or with song you like. No one can teach you how to "solo." That's something you need to discover for yourself. You can play scales and it'll sound like crap. Composing a good solo is something you have to find. Like I said it's not like someone can give you a lesson and "suddenly" you can solo well ( although it was enlightening for me when my teacher taught me that scales could be used for that). You have to find that out for yourself. Listen to cd's get ideas from other people's solo's try to copy them, make up your own style.