There are several EDM cultural traditions and behaviors that stand out as unique and very interesting.
1. Trading of/Wearing of "Kandi":
"Kandi" are bracelets made of different types of colorful beads that say various words. Kandi is often worn by people in attendence at EDM events and often the words refer back to various EDM related activities or beliefs. The trading of Kandi is an EDM tradition dating back to the late 80's and early 90s. The general idea is that when someone impresses you with their talent during some type of light show (poi, gloves, glowsticking, flowlights, hula-hooping) you give them a piece of your Kandi. Kandi can also be traded for reasons such as someone doing something nice for you or a new friend you meet in the crowd. The most interesting aspect of the Kandi tradition is the way in which it is traded. The person giving the Kandi will first make a peace sign with their index and middle fingers. The person recieving the Kandi will copy this hand gesture and place the tips of their middle and index fingers on the person giving the Kandi. The person giving the Kandi will then make half of a heart with their four fingers and thumb. The person recieving with again copy. The two people will then interlace their fingers like they are holing hands. At this point the person giving the Kandi slides the bracelet up over the intertwined hands and onto the other person's wrist. These three hand gestures represent peace, love, and unity, three of the aspects of PLUR.
There are many different forms of light shows. There is Poi, an ancient Chinese art in which two glowing balls are placed at the ends of two long peices of cloth sort of like tube socks and swung around in patterns in the air. Glowsticking has arguably been around in the rave scene the longest and uses simple glowsticks you can find just about anywhere. Flowlights are lights that slowly morph from one color to the next and are swung around in the air on string. Gloving, the type of light show I know the most about is done with white or black gloves with white tips that have a different LED light in each finger tip.