I broke my tibia/fibula at my right ankle a few years ago.  Now, that foot is a bit larger than my left.  For shoes that fit like a glove on my left foot, they're a bit too small on my right foot.  OR I recently made the mistake of buying AA shoes.

I've used the shoe stretcher three times, and it hasn't broken!  Other ones usually broke after two uses.

Now, this is going to sound strange, but it really helps if you *read the directions*.  That sounds like a no-brainer, but I figured that you insert in shoe and twist, right?

First of all, you need to pretreat it.  Spray with a shoe stretcher spray (I had some left over from when I had to stretch a boot) or spray/rub generously with isopropyl alcohol.  The isopropyl alcohol.is what is in the little bottle of shoe stretcher spray, which costs $5.  If you run out of shoe stretcher spray, you can fill the bottle with isopropyl alcohol.  Be sure to use 70%; 90% can be flammable.

So you pre-treat it, and place shoe in front of space heater/on heat register for about half an hour.  The heat makes the leather more pliable and helps stretch leather/suede.  Next, spray liberally with more alcohol inside/outside shoe, insert shoe stretcher, twist the mechanism at the end clockwise to stretch the shoe wider, and twist the disk counter-clockwise to stretch the heel.

Leave there for 48 hours, occasionally spraying with the alcohol.

When removing the stretcher, you have to alternately twist the handle at the end and the disk.  Twist the handle counter-clockwise; the disk, clockwise.  You don't just twist the handle at the end counter-clockwise and the shoe falls off.  You have to play with the disk a bit, tightening and loosening, as you unwind the handle at the end.

So, here are the directions:

1. Pretreat with alcohol
2. Place shoe on/near a heat source
3. Spray/rub liberally with alcohol
4. Insert stretcher and adjust
5. Place shoe on/near heat source
6. Occasionally spray/rub liberally with alcohol again
7. Adjust stretcher more if you can
8. Check after 48 hours

ALSO!  If your leather shoe fades a bit because of the heat, massage a very small amount of coconut oil in a buffer sponge or a soft rag.  (Coconut oil is great for leather shoes/bags/garments/brief cases, as well as skin/hair.  I highly recommend it.)  Rub over the shoe.  If the shoe looks very dark after rubbing the oil into it, the leather will absorb it, and in about 24 hours, the shoe will be back to it's true color.  DO NOT USE COCONUT OIL WITH SUEDE!