ABN or statement by supplier for affiliate marketing

Hi I’m looking for a lowkey side hustle and affiliate marketing sounds perfect. I’m doing it through Amazon associates via Pinterest. I want to do this the right way but an abn feels overwhelming and very official. Where as a statement by supplier feels easier and straight forward but if I earn over 75k I will be in legal trouble. I just want to test the waters with this business idea it’s very experimental I don’t expect much from it. I qualify for a statement by supplier but am not sure about an abn. A statement by supplier is basically an exemption from an abn form. What should I do, what do you recommend, please help!