Blast your heels with heat. Heat is an effective way to soften a material and make it more pliable. Carefully warm your heels using a blow dryer or a small heater for about a minute or two. Watch how your heels react to the heat because certain materials don't do so well under heat for long periods of time. You can bend and twist your heels while they’re still warm. Or you can wait until they’ve cooled and put them on with a pair of socks to stretch them.
Don't forget the heel taps on your shoes, either. "If you let those start getting to the point where they're chewed up, by the heel, or by just walking on gravel or stone, it's going to make it more likely that you're going to topple over, because if they're uneven, then you're going to be — literally — on uneven footing, so replacing those regularly, before they get bad, is important and that's going to help your shoe last longer too," Canfield McNish said.
Keep silica gel packets in your shoes when they’re not being worn. Have you noticed after purchasing a pair of new shoes those little white packets containing tiny clear balls inside your shoe box? Those packets contain silica gel which absorb moisture and keep your shoes from shrinking. Hold on to those packets instead of throwing them away and stick them in your shoes when you’re not wearing them. You can ask a shoe store associate for extras, if necessary.