As administrator you are able to create System Access Roles at Administrator> Advanced> Role Group Templates.
Create Role Group Template:
Click over Create New to create a new one.
Type the name of this role group at Group name
Then select the roles and the permissions that users will be able to do at the grid.
Click over Save Changes to create the Group Role.
Create a User using this Role Group
Select a User at Accounts
After select the user click over Edit
Select the option of Is System User at Security section. It will display a new drop list Role Group.
Select the Role at the list.
Click over Save Changes.
This user will be able to do the permissions added. Also this user gets a new role as System User.