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1. Present yourself well.  "straighten name tag, pops a mint and strides the crowd."
2. Do as much research as you can on the people attending.
3. Try and stand out with your outfit
4. Be prepared to give and receive business cards.  One pocket for outgoing, one for incoming, no fumbling.
5. Walk with purpose.  Look like you are having a good time.
6. Start at the food table.  People tend to be much more accessible around food.
7. Carry food in your left hand so you can shake with your right.
8. Circle the room once to read name tags and see if there is anyone you remember from your research.  
9. Approach VIPs and speakers before they present.  They will be swamped afterwards.
10. Try and talk to people who are alone.
11. Ask about other people, and when presenting yourself, say your name at the end so they are more likely to remember you.
12. Always shake hands at the start and the end of a conversation, it shows you are open and willing to talk.
13. Ask open ended questions to find out if the person will be of any use to you.
14. Be ready and willing to exchange business cards. 
15. Try and get someone to introduce you to someone new.  It is taken as an endorsement of you. 
16. Make sure there is some give and take.  Try and find out if you can help the other person with something, and if so, do it.  This makes they feel obliged to help you in return.
17. Remember that your goal is to not close any deals.  You are there to find a contacts that you can follow-up with, over a phone call or a coffee.