Help with oh baby baby booties

I have made this pattern before, but for some reason my brain can’t remember. At some point do you start knitting in the round? Thanks, Sherry

http://www.knitlist.com/01gift/oh-baby-booties.htm

I think the entire booty is made flat. The last line requires that you sew up the seam…however, I could be wrong.

It looks as if you do the entire sock flat and then seam it up, according to the last line of instructions. But, I could be wrong.

Unless I’m missing something I don’t see why you’d need DPNs at all since they do appear to be knit flat. :??