I don’t personally do much with affiliate marketing on Pinterest, but I’ll drop you a few links where you can begin to learn more.
Here is Pinterest’s Community Guidelines document. There is a section toward the end called, “Affiliate guidelines” and it will give you some basic info about the “rules!”
PBC member @isabeltalensm wrote a really fantastic response to a post about how to generate affiliate sales, too. It’s right here:
This thread also mentions the programs that are currently supported for adding affiliate tags to Pinterest Idea pins:
I hope these resources help a bit!