These days everybody has access to the internet, We see it's very beneficial for the company that salespeople have access to the inventory and their sales at any time, therefore, each salesperson need their own user name and password.
1- So basically each Salesperson in ZarMoney is a user.
This is where you can add and remove new users.
How to manage users http://help.zarmoney.com/en/articles/1452485-how-to-manage-users
2- Using custom fields
Now let's say you don't want to pay additional for each user and have them access ZarMoney; in this case, you can simply create a Custom Field and name it "Salesperson" .
How to create custom fields
You can also go to Advance print Section and to print the Sales Person name on your invoices.