Also being a self-taught crocheter (and self-taught knitter, quilter, tatter, etc), I have found that looking at illustrations from several books is sometimes necessary.
And that can get expensive....
However, for a situation like yours, when you just need an answer to one question, stopping by a library and looking at the reference books they have is extremely helpful. It can also allow you to test drive a book before you commit to buying it. To see if the illustrations and language suits you personally.
Also, never ever discount the value of trial and error. We learn through our mistakes, and sometimes those lessons are better than anything from a book! Kids know this, but adults sometimes forget, expecting instant success (and perfection).
My hubby's boss has a great saying "Never let the need for perfection get in the way of 'good enough!'"
Good luck, Hope the hat is nice and warm!
Caryn