Boss Overdrive/Distortion

I have this Boss Pedal that is overdrive and distortion...you can mix it however you like on it. I got it when I first got into playing guitar and now I don't really like it. Now I have two questions. First how would I set this thing to boost my already distorted crate amp up enough to solo over the rest of the band, and two...if I can't do that how much should I ask for it when I sell it.

I would use it as an overdrive and have the level up pretty high and the gain down pretty low and use the tone to make it stand out more. You probably wont get much of a volume boost, but it will make your guitar cut through the mix better. Just make sure the gain isn't so high that it muddies things up.