Oil pastels are inexpensive and loaded in color. They are a quick way to get bright, intense color onto your page fast. Eventually they will dry but it does take a long time.
If you have issues viewing the videos here on my blog please click the title of the video on the upper left of the video and it will open up in YouTube for your viewing pleasure.
With the above video, if you put acrylic over oil pastel, it will scratch off, or peel. It will stick better if you use watersoluble oil pastel. Just a word of caution. A very neat effect though. (You could do it with water colors in place of the oil pastels.)
(More videos after the break, having all the videos load at once was making the page load slow.)
Check out how he slowly builds up his layers with gentle hatching and lines of color, some of the color is hidden in the final image, but influences the tone of his image. Lovely work via practice and patience. :)
Again I've focused on stuff you might not traditionally see in art journals. Some of the techniques seen in the more "fine" art oriented videos are awesome and can be used in your art journal. Layers, scratching, using the texture of the page, adding stuff on top of the oil pastel.
I wasn't able to find a video on one of my favorite techniques, and that is to heat the oil pastel with a heat gun to make blending easier. Using care the pastel can be turned into a more paint like look. Be careful not to heat it to much. I'm not sure if they are flammable or not.