Using Acrylic Glazing Medium and Masking Fluid with Lizzie Connor - glazes are thin applications of transparent paint. You probably already use glazing in your paintings. If you thin acrylic paint with water to make it more transparent, then you are using a glazing technique. What is glazing medium for? Working with layers of acrylic paint, mixed with a clear glazing medium to create works - Glazing thins out the paint, increases transparency while maintaining vibrancy of colour, increases gloss and extends the paint, allows you to gently tint painted areas, and can help with blending and creating soft edges.