Baby clothes size help!!

Ashley • Follow my pregnancy on Insta: @ashandhads
Hey ladies. We're due with a girl in the first week of June. What size summer clothes should I be looking to buy? I want to get a bunch of cute summer dresses and tanks. I'm at carters at the outlet and right now my cart is full of 3 months summer clothes? Will that be the best size for summery style clothes? Thanks a bunch Xx