Look at what makes you laugh, what tickles your funny bone, find out why it makes you laugh then see if that can be applied to other situations. They do things, funny. This means that you have to look at how you could do regular, everyday things in a funny and entertaining way. To become a clown you have to look at the world through a clown's eyes. One good example of this is Gracie Allen, who took things literally to their logical ending.
Clowns make things funny at the expense of themselves, never at the expense of others.
To be a clown, you have to be a clown. Funny ones and unfunny ones. Whiteface clowns are the clowns that have their entire face covered in a base of white makeup and then have their facial features highlighted by colors of makeup. Whiteface clowns are often the more serious of the clowns, they are often skilled in doing certain items, be it juggling. They take pride in showing up the auguste clowns and tramps.