I've bought some nice brown leather flat pumps recently (which I'm rather excited about as I've not been able to buy myself anything for AGES) but they rub the absolute crap out of the back of my heels 
I know they are leather and will stretch/become more flexible with wear but I can't even bear to wear them at the moment.
Are there any tricks I'm missing with how to break them in a bit? They fit nicely but they come up quite high at the back which I think is the cause of the rubbing.