I crochet in one loop of the chain, then in the opposite loop. It is that simple. Baby booties start that way at making the sole.

Thanks. That is kind of what I thought it was. Except I was going to go in the loop under two threads as usual and then turn and down the other side and go under the one thread left in the loop. You are saying one thread of loop each way?
I had done a search and could find nothing regarding. Wish I could see a diagram.
Yes, it is a baby booties pattern I was looking at.

Yes, make that first row in one loop each way. Actually, that method you used will work too, but what I described will give you a more even look. I think of a chain stitch as looking like a chain link on top. Underneath the chain, there is a row of yarn bumps the length of the chains. So I usually crochet up one side of the chain link on the top, sc 3 times in the end chain, and then turn and go down the other side of the chain links. Then that "bump" underneath forms something of a fill between the two rows of single crochets.

If you are making a scarf or afghan, some people like to crochet the first row into that bump only so that the remaining chain on the top of that row row will match the last row of the scarf or afghan. Of course, if the scarf or afghan will have an edge crocheted around it, that first row doesn't matter that much either.

Hope this helps.

Does help, thanks! I'll do it the way you said - make the first row in one loop each way.