Assign Roles Tweek Role

Have a WP theme set up for a client. Want to give him admin roles but would like to limit what client can access so that he does not accidently mess up his site. When you go from admin to the next lower level (Editor), some of the functionality that the admin has goes away. The problem is that there is some of the functions that I need for him to have…like the ability to move the inventory order.

Any ideas or links to tutorials to accomplish this?

Thanks,

-Nick