There is an art, or, rather, a knack to flying.
The knack lies in learning how to throw yourself at the ground and miss.
Pick a nice day and try it.
The first part is easy.
All it requires is simply the ability to throw yourself forward with all your
weight, and the willingness not to mind that it's going to hurt.
That is, it's going to hurt if you fail to miss the ground.
Most people fail to miss the ground, and if they are really trying properly,
the likelihood is that they will fail to miss it fairly hard.
Clearly, it is this second part, the missing, which presents the difficulties.
-- The Hitch Hiker's Guide to the Galaxy