Our canvas was small, so first we cut all of our crayons in half. Then we lined them all up by color, so they'd have a nice ombre effect. We took out all of the neutrals & dark colors so the finished product would be bright & fun. We arranged them in a Mickey outline on the canvas, then hot glued them on (This part was the biggest hassle - The crayons kept moving before we glued them, & the hot glue melted parts of the crayons if we left it on too long).
After gluing the crayons down, we used a hair dryer to melt the ends & make the splatter effect. I don't know how anyone possibly does those fancy pictures you see on Pinterest, or how their middles are so perfectly clean. No matter what we tried, we got color in the middle section. I ended up painting it white later.
Here are some photos & a little video of the process! Just a heads up: the sound on the video is super annoying. I mean, it's a hair dryer, so you shouldn't expect anything different, but still.