Some great advice already.
I have 6 songs to learn for next Saturday so I'm in a similar, albeit easier position. Personally I set up a playlist on either YouTube or iTunes and run it from a laptop into my practice amp, plug in the bass and stick some headphones on. Take a few songs a day and add to a longer rehearsal as I start to build up.
Oh, and I'm sure this goes without saying but spending too much time on Basschat doesn't count as bass practice when there is work to be done!