Taped the corners of the card to keep it from slipping and used a palette knife to spread on the paste.
While the paste was still wet, used a trowel to create a textured design (could use a comb or plastic fork or cut credit card or other implement to make texture designs). I spread the extra paste over a dictionary page for future use. Let dry.
How it looks after drying:
Tried this technique with mixing two different mica powders (blue and green) with Gel acrylic medium over black paper, again spreading the extra paste onto dictionary pages.
Then tried the technique with a small amount of purple mica powder and a generous amount of copper mica powder mixed with Gel acrylic medium on a yellowish-orange paper: