Use of music, candles and crafts
Nothing beats live music, drumming, singing, guitar or harp.
Recorded music often works but often speakers are not efficient / loud enough to be heard in the wind.
Things we found that do not work well: lighting candles on a windy hill!
The Druids obviously used magic but we have found that in all but the calmest of conditions lighting candles in a group setting is troublesome..... even with candles in jars.
Getting people to bring something like a bunch of rushes or feathers? some do, some don't. So be prepared and have a reserve stock for the lazy ones.