To make this particular card, I sponged a variety of inks onto a piece of X-Press It cardstock. Here they are: Distress Ink Faded Jeans, Vivid Ultramarine, Distress Ink Fire Brick, Colorbox Cranberry, Mama Elephant Apple, Orangeade, and Sunshine pigment inks.
Once I was happy with the sky, I stamped the cactus image from Toybox with Versafine Onyx Black ink, and colored with a black marker to create a silhouette. I drew in the mountains with the same black marker along the bottom of the card.
White specks in the sky, unfortunately look like snow, but are supposed to be stars. Made with Copic white.