Not a desktop user? Check out the cloud article.
Go to Online.InkbookTattooSoftware.com and sign in.
Select Employees
Double click on the employee you wish to deactivate.
Select the Remote User Account tab.
Click on Deactivate Online Account.
On the window that opens, select Deactivate Account.
You may be prompted to delete the account if they no longer have access to any online services.