1. Don't drink too much or you'll be hung over for the talks. This is even worse if you're actually giving the talk - and I speak from experience. Conferences are jolly places where a lot of people feel let off the leash and the alcohol flows. It's part of the experience, but try not to over do it. (I will have to see if I can practice what I preach...)
2. Don't accost people, especially agents and publishers. Yes, you want to get published, but there is no way they want to receive your manuscript right now. Send it to them in the usual way, saying you've met them at conference is the way to do it. The tales of people feeding manuscripts under the loo door maybe apocryphal, but I have seen someone try to push their manuscript into an agent's tightly folded arms.
3. This is not the place to tell an author you think their covers are crap, as your opening conversational gambit. It's happened to me, and while you may think it's displaying endearing honesty, I didn't feel at all endeared. Use your common sense around published authors if you don't want their faces to freeze in a rictus smile. Generally I'm happy to chat to anyone, but I don't want to feel I'm teaching. Buttonholing me about adjectival use in the lunch queue is not good.
4. Make friends. Don't be so focussed on your own publication that you ignore other people. I remember going to Winchester and how some people's eyes glazed over when they realised I wasn't published and therefore not worth talking to. Ha! That conference I met Kate Harrison, then also unpublished, and we've been friends ever since.
5. Take lots of notes, and allow some time to write them up in legible form when you get home before you forget what they were about. I have notes for talks that I now can't remember attending, and some of them are in a useful form on my computer which I can refer to easily, and others are in a useless stack of paper on a high shelf in my office.
6. Have a good time!
Fancy a holiday in France with me? I'm teaching a week long course on Writing Mainstream Fiction at a fab chateau in the South of France in September. More details? Contact Chateau Ventenac.