Can I use regular varnish for Oil Pastels?

Answer 1

Yes, you can. But if you try brushing on varnish it might streak or run your finished artwork. You're much better off using a clear coat spray varnish. And use several light coats instead of one heavy coat and, of course, let the first coat dry before applying the second coat.

The most popular brand of clear coat spray varnish on the market is 'Kamar Varnish', made by Krylon. But there are other brands you can buy.