To follow up the work we did in class painting the sky, try again to invent a cloudscape with no hard edges. If you found that your paper dried before you could apply all the layers you wanted, try wetting both sides of the paper first. If you still see a hard edge, stop immediately. Dry the paper thoroughly, rewet it as efficiently as you can, and carry on making soft-edged strokes.
My approach leaves the blue for last (when there is blue), but you may prefer a different progression. Experiment. These sky scenes can be done pretty quickly, so make a few, and don’t spend time correcting. Clouds are very similar in feeling to transparent, fluid brushstrokes. If you poke away at the paint you will lose the simplicity and weightlessness of the forms, which are far more important than whatever is prompting you to fuss. The sky is a very forgiving subject. Just about anything can happen up there, so remember to detach from your agenda, and at least try to live with what your brush did on the first try.
If you are feeling ambitious, try painting one of these skies. Paint, though, don’t duplicate.