Tips on your tent:
1) Never put your tent away wet. Set it up at home and air dry it before storing. This will prevent the coating from being deteriorated by mildew.
2) Leaky tent flies can be revitalized with Nikwax Tent & Gear Proof. This puts a durable water repellency coat on the outside of your rainfly that helps shed rainwater. Listen folks --- there is no tent that we have found that is "guaranteed not to leak". Coleman's WeatherTec system is the best guarantee you can find.
3) Avoid prolonged exposure to sunlight. The UV radiation in sunlight can degrade nylon, causing fading and eventually weakening the fabric. Don't leave your tent set up in the backyard for days on end, and consider treating your rainfly with SnoSeal's UV Block.