The admin user will be able to add other users to the Frase account on the Team plan. To add users, log into Frase and click Account-->Team. Then, add the email address of the user you'd like to invite and press Enter.
On the Team Plan, you'll be able to have 3 users in total on the account including yourself, but each user invited after that will cost an extra $25 a month. So make sure if you invite someone, that person accepts the invite, or if not accepted, click the trash can icon to delete the "invited user".
If the invited person isn't seeing the invite email come through on the first invite, and if it's not appearing in Spam, try deleting the user from Frase's Team page and inviting again. Reach out via this form if there are any further issues.
Note: once the invite is accepted to be a part of the Team, the user can create their own documents, or if you want to make certain documents in Team visible to the user, make sure the user is added to the folders where those documents reside. Select the folder and click the pencil icon to edit user access and other information.