Many people publish advice for cisco live attendees, hopefully new information here. I have been a regular attendee since 2000.
1. If you take a techtorial (sic), bring an old 1 gig flash drive. Often the speakers do not have their current slides uploaded to the site on Sunday and so a flash drive is a passed around the room. We all have old 1-2 gig flash drives that are smaller than we normally use, bring one and you first get a copy of the slides early on, and also help the rest of the room.
2. See if the sessions you want to attend are already on cisco live 365 you can check out if the session is right for you and have the slides before you go.
3. bring and extension cord with extra outlets, power can be hard to come by but someone may share their outlet if you don't need them to unplug.
4. Don't schedule that really heavy technical presentation you need to see on Thursday afternoon, you will be tired.
5. Have software that lets you highlight or annotate the PDF slide decks (depends on your platform)
6. AC can be rough have a sweater or sweatshirt with you
7. Make use of any lounge you can (netvet, certification, collaboration) its easier to get a seat and maybe a drink when you need it
8. Ask questions but project your voice (big room) and try not to tie up the speaker too long. Some of the best stuff is at the end of the talk and you don't want the speaker to rush through it.