This is a noble goal. Treat your suit with love and respect and it will return the favor when the time comes to wear it. Suits should be hung, on a quality hanger, in a space where air can circulate. Make sure your suit is aired-out and clean before putting it away. Herewith, some long-term storage tips.
Your jacket may've come with a plastic hanger, but you should spring for a well-made wooden suit hanger. These have a substantial shape to the shoulder and arch forward slightly, which supports and maintains the shape of your jacket's shoulders.
Suit hanger, $12
at The Container Store
The last thing you want, is to pull out your suit and find that your pants have been rumpled at the bottom of that suit bag for the past three months. If you're not keeping your suit in a bag, felted clamp hangers (clamped at the hem of the pants) will ensure a smooth finish. If you are keeping your suit together in a bag, then employ the "Savile Row fold." Developed decades ago by London's best suit tailors. Grab the pants by the legs and fold one through the hanger until the hem reaches the crotch. Finish by folding the second leg similarly over the first.