We run the affiliate programme on the Partnerize network under Plum Guide where we have 4 key markets onboard (this correlates to the currency you wish to be paid out in, as opposed to where guests book from):

Select which campaign to be a part of in the campaigns section of the partnerize platform. This article near the bottom explains how to do that (ensure you are logged into Partnerize)

Once your application has been approved, you are ready to start promoting the brand to your audience.