I found the original tutorial here, but made some amendments to make it my own. Here we go!
1) First I bought a really cheap canvas, and a $1 box of crayons. Crayola has prettier colors, but their crayons cost approximately six times as much as Craft Store Brand crayons, and I don't think the colors are six times prettier.
2) This was - no joke - the hardest part. It's possible that non-discount crayons come out of the box already all lined up by color, but that's something that's included in the other $5 that I didn't spend. So all the crayons in the box were mixed up in no logical order. I took out all the blacks and browns because those are downer colors, and proceeded to line all the rest of them up in some sort of color order. This took me about a day. I would line them up on the ground and walk away. And come back and think, "what kind of blind person put that color next to that one, when it clearly goes over here?" And then my dad would come by and kindly inform me that I was obviously colorblind and this was a shade of indigo, not blue. Etc.
3) Once they were lined up to the best of my abilities, I took a hot glue gun and made a little strip of glue on the canvas. And stuck down the crayon. And strip of glue. And crayon. Approximately 50 times.
4) This is where I start to deviate from the original directions...they suggest using a hair dryer to heat the crayons, but I disagree. My brief attempt at using a hair dryer caused a momentary severe panic attack when pink crayon wax started to fly everywhere. Which leads me to the next step...
4b) Put down a dropcloth/plastic bag/anything. You'll need it, trust me.
5) Once that crisis was averted, my brother bought me a tool akin to an embossing wand (I'm fairly confident an actual embossing wand would work too). This was great because it blew really hot air at a very low speed. This gave me a lot more control over where the wax was going. This step actually goes really quickly - the crayon wax doesn't melt...doesn't melt...doesn't...then suddenly gets shiny and melts really fast. It was kind of like a game - some of the drips started going down the canvas too far and I would zap them with my wand and stop them in their tracks. Super fun. I played around with trying to influence the direction of the wax trails, etc. This step is a bit of a choose-your-own-adventure, so you can play with this as much or as little as you want.
Now it looks like this:
6) At this point, you can pretty much do anything. You can leave it. You can buy another pack of crayons, flip it around, and do the other thing from the other side. I chose to use some left-over fabric paint and stencils from a different project to paint a quote over the whole thing.
So anyway - that's it! There are a million different approaches you can take - I'm keen to try some smaller single-color ones over winter break. But this is the basic approach! Good luck!!