This is one of my own ZIA pieces.
The outline template is one by Ben Kwok.

When I do a ZIA project, I try to use patterns that will enable me to use shading when I come to add colour.

Some patterns I can get to work well when I add colour and helps me improve my shading, however, other patterns I struggle to get any shading to work.

Colours, I often like to use contrasting colours to hightlight my designs, this one I used yellow and blue. The yellows are very pale, and those sections look almost uncoloured.

I now offer my designs for Free, uncoloured, for colourist who would like to use them - Free Zentangle Colouring Art and Collage Art