When breaking your participants into Groups, use these 'quick-sticks' ideas:

1. Hair Colour - light & dark & inbetweeners

2. Birthdays - quarters of the year; or halves of the year; or if you have a large group, months

3. Numbering - have them number off, from 1 to 4 or 5 etc. depending on how many groups you want to work with.  Then all the '3''s pair up, and the '4's etc.

4. Corners/Points of Reference - play some music and have your participants walk around the room (you will engage every learning style doing this).  When the music stops they go to the corner of the room that is closest. For groups larger than 4 incorporate points of reference - doorways, windows, presenters table etc. as well as room corners - be adaptable

5. Teams - let people choose their own partners via favourite football teams, sports they enjoy, high schools attended - some common point of reference

6.  Pets - Who has dogs?  Cats?  Both?  None?  Horses?  etc.  Even the team numbers up once divided into groups, if there are more dog lovers than cat owners 

7. Incorporate stickers, or playing cards or raffle tickets in their workbooks or on their name tags/lanyards, or on their chairs and use them to help you group throughout the day.  

THE SECRET:  CHANGE GROUPS REGULARLY - increase networking, ideas, energy, output, familiarity, confidence, and control of participants (breaking up cliques !)