Trouble with Buttonholes

I've been working on a top to match one of the pairs of Knot No-Hem Pants I made a couple days ago, but I can't seem to get it finished.  Why, you ask?

Buttonholes.

I've never made them before.  I have an automatic one-step buttonhole, so you'd think it would be easy, but I still haven't had any success.  I read the manual and followed all the steps.  I called my mom.  I consulted about a bajillion tutorials.  Everyone's giving me the same information, and I'm like 99% sure I'm doing it right, but they still look wonky.  I guess technically some of them are buttonholes.  It's just that the little zig-zags look like they wouldn't hold up after a couple times buttoning and unbuttoning.  Plus, every time I made a buttonhole they seem to turn out differently.

Finally, I got frustrated practicing and said, "I'm just going to do it on the shirt!"  Well, it turned out like this:

So crooked!  (Okay, so that's probably my fault.)  And now I'm going to have to find out some way to salvage the shirt because I've tried using my seam ripper on my oopsy-doopsy and couldn't get it out.

Any one else had a lot of trouble with button holes before?  Any tips?