Thanks guys for your replies no baby shower for me ,so the earlier I start buying stuff the better.

Well, any time really. But personally I waited until I was 4 or 5 months to buy a few things like the car seat, electric pump, a bunch of clothes, etc (because I got a great deal from a generous mom who sold me her gently used items for $40) and then I didn't buy anything else until after my baby shower which was at 32 weeks. I'm almost 36 weeks now and am going to go buy some more items we need today and then the rest my mother in law is getting for us in July.

Whenever you want!

I waited until after the baby shower. If no shower I'd wait until after 20w

I bought some supplies when I found out I was pregnant and clothes when I knew the gender, but it's really just up to you!