The_Complete_Guide_to_Facebook_Marketing

For customer lists, you can export your mailing list subscribers, customer database, or other email lists
you have. For website traffic, you will need to add a pixel to your website or specific pages you want
to create an audience from. For app activity, you will choose an app you have created (such as people
who have opened your app) to extract users from.
In addition to creating new custom audiences, you can create lookalike audiences.
This allows you to target people similar to another custom audience you have created, such as
Facebook users who are similar to your current customers.
The Complete Guide to Facebook Marketing
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