1.Have a plan. Know in advance whom you want to meet (directly or the type of people), which speakers you want to hear, and what tradeshow booths you want to visit.

2. Set appointments in advance.
If you know that there will be people in attendance whom you know that you would like to see, call or email a few weeks in advance to schedule a time to meet for coffee, a meal, or a drink. Do not hope to "run into them", as your paths might not cross at a time when you can spend quality time together.