Shipping Profile help?

[JuicyMocks]

I have a item that will be 8 oz at first class 

If a buyer buys 2, it will no longer be first class, it will have to be upgraded shipping due to weight.

How do I set up a shipping profile to reflect that 1 item is first class but has an upgrade shipping option

AND if they buy 2, it no longer shows first class shipping rate, it shows upgraded shipping and the upgraded shipping price. I've seen sellers do this, but I have no idea how to do it ! 

Thank you sooo much 

[NanaLetha]

First Class package is no longer an option. Ground Advantage has replaced it. You can mail up to 70 lbs that way.

[PlatypusDream]

https://help.etsy.com/hc/en-us/sections/360003399774-Orders-Shipping?segment=selling

[LoonMtEmbroidnCrafts]

You can add an amount for a second item when setting up shipping profiles.