DIY FAIL (or, why you should always follow instructions)

Oh yeah, you know how I was saying that I'm pretty crafty? Well, maybe not.
I went to one of the bridal Meccas, the one known as Michael's, to buy some Vitrea paint. My local store only had the porcelain paint. I figured it would probably work the same. My local store also did not have the thinner that the instructions tell you to use. Did that stop me? Not at all. I decided to do a test run on one of the bottles instead of ordering my supplies from *Amazon (because that would require patience, a virtue that I lack).
Having seen other projects done with Vitrea, I knew that it would be streaky before it was baked so I wasn't too bothered with my bottle's pre-baked appearance. I waited twenty-four hours, popped the bottle into the oven, and was left with this:

No. 

This isn't what I wanted at all. By this, I mean a streaky, poopy-looking bottle. My crafty skills have failed me. This is why it's always better to follow instructions! Do not be like me, do not say, "thinner? I DON'T NEED NO STINKIN' THINNER!"

Just buy the thinner, for crying out loud!

I guess it's back to the drawing board for these.

Have you had a DIY fail?

*As a side note, if you're thinking of using Vitrea, you might want to move fast. Michael's had all of the paints on clearance and were almost sold out. When I asked if they would be restocking, they said they wouldn't. Amazon is still selling it but they cost about $11 per little bottle of paint.