It depends for me, if it's a regular sunny/cloudy day with not much change, I'll set it, check while I'm shooting that it looks decent, and continue on.
If a show/parade is starting and the clouds keep covering and then exposing the sun, or I'm shooting something like FOLK, Fantasmic, etc, I'll throw it on Auto and deal with it later, too much to worry about and not enough time to worry about changing the settings during a shoot like that