All you have to do is visit macaronigrill.com and sign up for their newsletter. But this won't work if you need this coupon last minute as this one might take up to 24hrs for you to receive your $5 off coupon so keep a look out for it.
Did you know you could order online for pick-up? For Individual entrees all they need is thirty minutes to prepare your food and you can pick up your order on your way home from work. Check it out http://www.macaronigrill.com/online-ordering
Eat Well & Adventure On,