First off, find a website that you like to edit / make skins with.
Second, make a square with the desired colour on the first layer.
Third, go on the outer layer, and find a different shade of that colour.
Fourth, add petals on the top, left, bottom, and right of the square.
Boom! You've made a flower!

Tips. Make sure the shade of the colour for the second layer is still close to the first one. If you want to make multiple in a small space, fuse the two squares together, and then follow the rest of the steps accordingly. This also works if you want to make a line, or flower crown of flowers.

I know you can do this, now get out there, and get creative!