A media buyer posting as Albert wrote a long guide on r/PPC off the back of eight years and, he says, close to $100 million in ad spend across the companies he has worked for. Most of it argues against clever setups. The part worth lifting is the arithmetic he uses to size a test.
The strategy
His testing structure is one ABO campaign, with each ad set holding two to four creatives and a daily budget equal to one times the product's CPA. His example uses a 40 euro CPA, so each test ad set runs at 40 euros a day. Targeting is broad with no interests, one country at a time, both genders, 18 plus. If you want more volume you add ad sets rather than creatives, so 160 euros becomes four ad sets at 40 rather than one ad set with twelve ads. He notes that if you would rather test slowly, extend the days instead of raising the budget: four days at 40 beats one day at 160.
Evaluation runs on the ad set, and the thresholds are fixed. Zero sales, kill the ad set and try a different visual approach. One to three sales, hold one more day, and if it is profitable pull the winning ads out. Four or more sales, it is a winner. In every case the ad set dies once it has done its job, while any individual ad that made a sale graduates into the scaling campaign. He is blunt that the ad set exists only to tell you which creative deserves real money.
Two related points. Your CPA ceiling is what the margin permits rather than what you would like to pay: on a $100 product with a 37 percent margin, a $22 customer that people panic and kill for missing a wished for $12 target was making $15 a sale. And he says a winner usually starts creeping up around day three because the same people have seen it, so testing runs alongside scaling permanently, feeding three to five new creatives every 72 hours.
Why it works
A test ad set funded at one CPA a day should buy roughly one conversion a day if the creative is average, which makes the zero, one to three and four plus buckets readable within a few days instead of a few weeks. Splitting budget across more ad sets rather than more ads inside one keeps each decision attached to a single unit of spend.
How to structure Meta ad sets for creative testing
Take your break even CPA, set that as the daily budget for each test ad set, and put two to four genuinely different creatives in each. Judge at the ad set level on the sales thresholds, keep the ads that sold, and start the next batch before the current winner slows.
Credit: u/silveris203 on Reddit