First you will want to ensure you have a Distribution Group Created. To create a Distribution Group navigate to:
  1. onMessage > Communication > Pushpage > Distribution Groups > Create Distribution Group
  2. Give the Group a Name and select at least 1 Static User (you can remove after the import)
  3. Save

Then navigate to:
  1. Core > Settings > Data > Data Import.
  2. Pushpage2010 > Distribution Group - Static Users.
  3. View  the File layout help to determine which layout to use for you data import file, distribution_group, user_id or distribution_group, firstname, lastname, host_id.
  4. Click Add Job to add the job.
Note: If you do not have the Host ID or User Ids in the CSV file, then you will need to manually add the users to the Pushpage Distribution Group via a list or individually as static users. Pushpage jobs can only be sent to constituents in your database. There is not a way to send a pushpage issue to someone that is not in our system.

Users must be part of your database to receive pushpages so that they have the option to opt out of the emails if they choose, per the CAN-SPAM Act.

Having users in your database also allows you to track a user's Pushpage Job History.