I've stocked up on sunscreen for the nice weather and I've read the backs and they say 6 months! I think that another good thing would be a nice hat with a large brim, or a tilly hat. They are great to cover the face as well. I also have been using little baby sunglasses for my little guy, they are sooo cute and he doesn't actually bother with them either. They are great!! Remember their eyes too!
Once they hit 6 months they can wear sunscreen
I spoke with a pediatrician about this last week. He said 6 months is a good guideline. But the most important thing is to reapply, and don't think that baby can sit out in the sun all day like adults can. And any sunscreen for babies should be fine. Of course, the higher the SPF, the better.