Basics: Using oil pastels

Here are the basic techniques used in oil pastel painting, shown clockwise from the top left: blending by short strokes (light touch pressure), blending with heavy pressure touch, scumbling, tinting with white, toning with black, scraping away, and finally, stippling (broken colour or optical mixing as it is also known):

The images below show the technique of blending using turpentine substitute on top of single direction hatching (see also above image, top left corner for hatching).  In the images below, after the foundation colours have been applied using the hatching technique, they are then soft blended using a cotton bud dipped in turpentine substitute. The cotton bud is handled like a brush and it is important to use only light pressure to blend the colours. Once done, both steps are repeated as a continuing process until the painting is done. Finally a few highlights are added using the pastel stick directly on the surface. NOTE: you can use water based oil pastels and blend using water if you prefer. Carand'ache's Neocolor II series of water soluble oil pastels are a good choice.

Here the first stage is complete. It is now ready for the second step: soft blending with cotton bud dipped in turpentine (NOT white spirit).

To show the contrast between the two basic steps that make up this procedure, the left side shows the soft blending whilst the right shows how far the image is developed in the first step.  Next step is repeat this process.