Trust your histogram and EV indication or shoot in Auto mode. It is very difficult to give general recommendations other than to suggest shooting at the lowest ISO possible to achieve TV of twice frame rate or higher for video or to stay below 3 sec in a hover (faster in flight) for stills. Your available exposure metering indicators will prove significantly more useful than guessing what the particular lighting of a scene might be.
If you are asking, auto is probably best to work with until you know what you are doing with camera settings.
Auto will give you pretty good results most of the time.
If you don't know what you're doing and try to set things yourself, you have a higher chance of messing things up.