happy to see your success
lot of people get intimidated with buying ads
usually you can get started with the same simple strategy
find an offer on your cpa network
google/bing it with adblock off
go through the sponsored ads
rip the entire landing page...start tweaking it. there's even paid tools that will tell you all the KW's the competition is bidding on
put the tweaked ad up on your media buyer panel
you usually willl make some sales, but whether the campaign is profitable is up to you to tweak.
rarely is it profitable off the bat. hence op mentioning testing 4x landing pages concurently.
for those tripping on they must do this with maxbounty -- you can do this with any aff network. you may be on one already. or can get into one that's easier tthan maxbounty. clickbank for instance accepts majority of people (so long as your country is not on their shitlist) and everything there is a big paying cc submit offer that always has people bidding on keywords.