Never pastel on wax

Today's chapter in my drawing-lab-book: painting a portrait with pastel areas. They suggest to mix it with colour pencils but somehow my hand went to the wax crayons. Wrong. Pastel does not paint on wax. I should have known it. It was interesting doing it and it is a lot of fun getting your fingers dirty with colour. But I don't think I will use that technique much.

And again: I didn't want to let the things like this before going to bed, so I came back to my favourite technique of the month and drew the girl above.