I´ve been looking on the forum and other sources about media buying and I can not find a good guide or tutorial on how to effectivly test ads on PlugRush or other networks in order to find out what works without expending big budgets with no results. I don´t think this is something easy to find, since media buying is where big money is and nobody would give you a secret formula to find winning ads and campaing settings with 500% ROI hahaha. But please let me know if anybody knows a good tutorial. Thank you!!