I would add 3b. Introduce yourself at the conference -- many people are at Global Forum on their own. With close to 4,000 people the conference can be overwhelming when you are on your own. If you see someone who looks lost and a little bewildered, stop and talk to him or her, ask if they would like some help. If you see him or her later, ask how they are doing. If you are on your own and see someone with a lot of ribbons do not hesitate to talk to him or her. Most of us do not bite :) I know I sometimes draw the ire of some of my colleagues because I am almost always late for a some event at the conference ("the even later than normal Peter"). By stopping and talking to people on the conference floor I have not only made several new friends but also gone on to collaborate on papers and work with them.