The ribbing should make this hat work for a lot of head sizes. I'm hoping it will fit from newborn to 3 months or so. The pattern is available free: here. I used up some Louisa Harding Kashmir Aran I had left from knitting Marmalade. The color is called "frost" which seems appropriate for my January baby!
I altered the pattern slightly as I got to the top decreases. I decreased more rapidly as I wanted a rounded shape and it seemed like it was going to get rather pointy if I continued to follow the pattern. But either way would be cute. I think a pom pom could be nice on top, but it's doubtful that I have enough yarn left for it.