Diane Mannion, CRUET, Snippet #18, 3.5x2.5" oil on linen/mounted
It's a relief to paint a piece of glass that doesn't look like a peanut, lady, or a mysterious character. It's simply a small cruet found in an antique shop by my brother-in-law last year.
Glass is easier to paint if, like anything else you paint... SQUINT while looking at it. Squinting helps simplify the values and shapes. I have SQUINT! printed on my paintbox to remind me.
Try to see shapes and values and don't think that you're painting glass. Same thing applies to anything, (especially portraits) simply look at the shapes, values, and colors. See the patterns.
If while you're painting, you stop and think... YIKES, I'm painting GLASS! You'll be lost.
Relax. Drawing/painting is meditation. Be in the zone. Let your subject show you what it is.
I often tell my students: "If I can teach you to see, I can teach you to draw and paint." And I always add, drawing is painting and painting is drawing. No matter what medium you're using. Look at that apple, for instance and SEE how it is different than any other apple. It does not look like the apple that a child draws in kindergarten.
Now go paint some glass and really SEE it. And don't forget to SQUINT!