I've only been to two conferences: PLDI and OSDI both in sunny San Diego. I don't think this should be a iron-clad guide, just a few observations I and my fellow students had. Admittedly its not a lot, but eh can still learn enough.
1) If your paper is accepted, always add acknowledgements. Who funded you? What are the grants? Otherwise your sponsor will ask you, why didn't you put me in the acknowledgements.
2) You can go to a conference for free! Yes absolutley free! Apparently most conferences have travel grants for students as long as you have a real reason of going. USENIX OSDI sponsored all 160 students. So who knew they were swimming in money? Might as well jump in the pool. The travel grant applications are due about a month or two prior to the actual conference date.
3) Poster and Works in Progress sessions are useful to see what people are doing. Sure there is probably information on the web or a paper, but what is more entertaining? Talking to a person and finding out what they are doing in 5 minutes or scavenging Google.
Anyone else have some tips?