In Squeezely you can add users as follows:
Go to Users (in the account where you want to add the user)
Click on 'New User
Enter the name and email address of the new user:
Select one of the following permission levels:
Account editor: can do anything in the account, except view and modify the account settings
Manager: can do everything in the account
(Agency option) Master Account User: can do anything in the accounts, except view and change the accounts' settings
(Agency option) Master Account Manager: can do everything in the accounts
Click on 'Create User