Some cool things to do if you have nothing else to do, are the following:

If you're smoking somewhere inside, by a window with blinds, or anywhere that lets small streams of light through, smoke near it, and you'll see amazing patterns within the smoke swirling all around, only visible in the streams of light. it's really cool.

Another thing to do, is practice blowing smoke rings. They are fun, and it's now a habit for me, whenever I'm smoking, to blow a few smoke rings. It takes some practice to figure out how to blow a ring, then you'll be able to do it occasionally, but with practice, you'll be able to blow kick ass smoke rings.

I agree, with whoever said to keep your journal on this thread. It will eventually be a lot of pages, but you can look back at your evolution, and as keep everyone's advice.

Also, everyone so far has given great advice, so you're definately well prepared. Good luck, I'm looking forward to hearing how it went.