DIY projects with faux finishes is about the most rewarding activity I know. There is nothing finer than making a cheap collection of wood,paint and other bits and bobs look like they cost you a million dollars.
This is easy but so effective for ceilings.
First paint the ceiling with two coats of sky blue paint. What constitutes sky blue is your decision. A little purple in there creates a more mystical feel
Try one of these shades
Allow the ceiling to dry.
Dampen a synthetic sponge (never use real sea sponges for decoration) and
squeeze to romove drips . Dip your sponge in a blue-grey paint mix and splodge
it on the ceiling (avoid drips).
Before it drys, scrunch some soft rags into a ball and dab them on the fresh
paint repeatedly to soften the edges of your clouds.
Now here is the secret...
Sponge some much lighter blue paint around the clouds and dab with scruched
up cloth as you did before.
Then repeat this process again with off-white paint, but only round one
side of you clouds.
That's it.