If you're an Admin on OpenWrench, you can add a new user by going to the Users page.
Clicking Invite New User. Put in their email, name and role and you can send them an email invite to sign up and set their password.
Depending on the role, you may also need to select the location(s) that they will need access to. This list will act as a filter determining which locations' information they can see across the application.