We started right away. He only lasts maybe 2-3 minutes each time before he starts fussing, but we do it every day. As PP said, you might try doing chest-to-chest, especially in a reclined position. Just make sure you don't fall asleep like that.
Dr was recomending starting it at 1 month check up. When you're starting to not just want to cuddle them all day long and actually let them be separate.
Re: tummy time