Painting white and transparent objects is easier to do if you know your correct values and can 'see' white as shades of gray. In this demo Christine helps students understand the in-person colorful grays and how to make glass sparkle. Although this demo is in oil, any media can be used as this is done with 'direct painting' and no layers.
Set up your own still life with white, or nearly white objects in strong light. Sunlight adds an extra layer of excitement to the project as it will be changing, so the timed nature of the project will foster looser brush marks and encourage a 'no overthinking it!' mindset. It may feel uncomfortable to start with dark looking and drab grays but this is what the painting will require to have the subtle color shifts of white in shadow and the sparkle of the glass vase. (Only 5% of the painting is a bright white or light value).