Glazes are the opposite of washes. Just as a wash gets into teh cracks to provide shadine, glazes are supposed to remain on the top most parts to provide a highlight.
You want less water in the water

aint ratio, and you only want a small amount on your brush. Paint it lightly on the top most edges of a model and let it dry.
I don't use them much. Not many people that I know of use them at all.