This is what I learned at AWA2016 (long list)

How to earn the most with Facebook Ads:
First, make a list of at least 200 of your premium buyers. Not just your buyers in general: take only those persons who bought from you the most expensive products and who didn’t return them. Upload them on Facebook as a custom audience. Then, build a 1% lookalike audience out of it. Facebook will take a look at 2000 data points for every person and will give you a huge list of persons who are very similar to your buyers list. That’s the list of persons who is the most likely to buy from you.
Create a landing page and send those Facebook users to the landing page. Upload a Facebook remarketing pixel and a Google remarketing pixel on that landing page. Buy remarketing ads on Google and on Facebook for those who have visited your landing page.

Start one new campaign every day. The profit is in a large amount of campaigns.
Top affiliates often have 200+ campaigns running at the same time.
Start with 10$ per day per campain and let it run for 7 days. If you loose money, stop it. If you spend as much as you earn, narrow it down by gender, age, mobile vs. desktop, country, or region.
If it goes well, go from 10$ to 25$, to 50$, to 100$, to 250$, after each weeks.
Expect to see a decreasing ROI if the volume increases.
Go from 1% lookalike to 2%, to 3%, to 5% and finally try 10%.

Try video ads and text ads.
If you do a video ad, try to film it with a phone or ad a filter, to make it look less professional. That converts better. Always add a subtitle, because people often watch Facebook videos in public without sound.

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