If your shoes are wet, stuff them with newspaper ASAP and keep them away from direct heat (which can dry the leather too fast, causing it to crack and loosen adhesives.)
Throw out the shoe box. Storing leather shoes in its original packaging for long periods of time will do harm to the materials (thanks to humidity). Keep them on a shoe rack instead.
Give them the day off. Wearing your chestnut brown wingtips three weeks straight is definitely not going to prolong their life. Every few days give the shoes a chance to "breathe".
Use a shoe horn. That foot wiggle dance you do when trying to get your shoes on destroys the heels.