Supplies needed: white construction paper or cardstock, scissors, markers/crayons/stickers/other supplies for decorating, googly eyes, glue, curly ribbon (or yarn or other item of choice for the tail), feathers.
I used cardstock (8.5x11). First I cut out all the parts of the body: for the main body, I just rounded the edges of one sheet of cardstock. The legs were made from about half a sheet of cardstock and the head was formed out of the other half. Also cut out a small rectangle for the neck and cut out the unicorn horn. (We didn't place ears on it due to some time issues.)
Big and Little Sis colored the "torso" first and also used stickers. (Big sis was determined to color every square inch this time, so little sister wanted to do likewise...they both enlisted Mommy's help for this!)
Finally, she wanted to color the unicorn horn and glued it onto the unicorn head.
I had her choose ribbon colors, then I did the tail part (partially due to limited time) - curled the ribbon and I ended up just taping it on.