If you want your client to authorise timesheets using the ETZ Sign/On line method you will need to create a new user record on the system for the relevant line managers/timesheet authorisers.

In order to do this you will need to select Client User Entry within the reference data tab.

When you select this option it will provide you with a client user summary. 
To add a new client user entry (timesheet authoriser) click on Add new Client user button. 

Enter the relevant name and authorisers email address. This email address will be used to communicate to the client through key points of the timesheet authorisation process.

Only enter the client’s mobile number if the client is happy to receive SMS messages. The mobile number must be entered in the international format as displayed.

You will see the log in allowed button is ticked and you need to ensure this is in place at all times to allow the user to gain access to the system and authorise timesheets.

Under the roles section you will need to select the client tick box and click Save Changes, this then initiates the client record which you now need to attach to the client.

You will be able to attach the client by Clicking on the drop down arrow and selecting the client accordingly and then click on Add Client, then Save Changes.

Once the user has been saved it will take you back to Client User Entry summary screen. 

For more details about the Client user roles 'Client' and 'Client Admin' please refer to the following article:  

What are the Client and Client Admin Roles for?