What do we do when things go wrong? If you become a bit exuberant with the pastels and think you've ruined your painting and wish that you hadn't put some marks here or there. You can correct your mistakes, providing you haven't sprayed them in.
Putty rubbers are good for small areas, pulling off pastel.
You can use tissue to brush off the pastel. But be wary, this is going to really smudge everything, so unless you are desperate to get rid of an area try to find a way around it.
Some people use a stiff brush to brush pastel away from a large area. It comes off the paper 90%. But what happens is that if you've rubbed the colour into the paper for the underpainting, it stains the paper and you are left with a dullness to the paper. This loses that vibrancy that you've been busy trying to capture.
If the pastel is more surface painting, then you can successfully remove elements and repaint them. I made a painting with a wall running all the way across it. I hated the wall, so I did some demolition on it, and painted over the area and you couldn't tell. Once I even spilt some milky coffee on the painting, right in the sky. I blotted it with tissue and when it was dry was able to apply the pastel over it and work it back into its surroundings. Phew! You couldn't tell. It all adds to the personality of the painting.
In my
autumn painting, which you can view in the gallery, I added a girl to the picture and didn't like the feel of it and so
painted it out.
Here are the images with and without the girl. This demonstrates that it's easy to alter elements in your painting. This is the full image.

Once, however, I had some really dark shrubs and grassy subjects running along an edge and it looked really good, I was happy with it until………. I realised that it was on the wrong side. I couldn't think of what to do to the opposite side to balance it up. I brushed it, puttied it, did everything and it left a dark stain on the paper which I couldn't manage to blend in again, then I wished I'd have just left it. So to the extreme I chopped off the painting.
As you become more experienced, you'll know what you can alter and how you can alter it. One good reason for a plan before beginning the painting!
bravenet.com