You can easily add another user and give him access to the Procon Layer and the server.

Once you are connected to the Procon Layer, simply navigate to the "Parental Layer Control" → "Accounts"

You will already see your account and on the bottom you will have an option to create a new account.

Write the username and password for the new account and press the button "Create account"

Once a new account has been created, it will appear on the list.

Do have in mind that the newly created account does NOT have any kind of access or privileges by default.

Adding privileges to a newly created account

Once you create an account, he will not have any access.
To change this, and give him the privileges he needs, simply click on his name on the list, and press "Edit account"

Simply add privileges to that account and once done press "Save Privileges"

You are done. You have successfully added a new account to the Procon Layer! Depending on the privileges that the account received, it should be able to connect to the Procon Layer and/or use in-game commands.