Another important factor in levitation is the Sun.

It's not the sun's gravity that matters... it's the light. I can really only levitate with reletive ease on certain kinds of days. It must be clear and sunny but not intensely bright. A light haze such as you get on a summer morning before the noon of a hot day is perfect.

It's possible to float in brighter conditions but it's a lot harder to get the feeling right.

Floating on a cloudy day is possible but anyone who has tried it rarely bothers a second time.