Create a customer file audience in the 'Audience' page in backstage.

1.  In the left menu in Backstage, click on ‘Audiences’ > ‘New Audience’ > 'From Customer File' to upload a customer file
   
   
   
   
2. Upload a CSV file with hashed emails or mobile advertising IDs of US customers
   
   
   
   
3. Choose the hashing type or mobile advertising ID and name the audience
4. Click "OK"
5. Files appear in the audiences table with "Processing" status
   
   
   
   
6. After 2-3 days, the lookalike audience status will change to "Ready"
   
   
   
   
7. When it's "ready", target or suppress the audience under My Audiences on the Edit Campaign page
   
8. Once a campaign is targeting an audience, the status of the corresponding audience will change to "Active"