I forgot how demanding clear glass is to paint! It is not unlike cat whiskers, patience required! Notes to self (and you if it can help:) Getting caught up in detail is a likely hazard, so paint big shapes first, small shapes as needed. Glass amplifies darks and lights, try to see those first and do not stress about color too much. Whatever is behind clear glass shows through it (shocking, I know.) What actually shows through is both lighter and darker than behind, conserve "background" paint on your palette, so you have enough when it's time to paint the glass. Clear glass contains a plethora of alternately soft and sharp edges, identify accordingly. Pure titanium white is your friend when painting clear glass, but save it for last.