Such a trouble recently happened - I bought leather demi-season boots daughter. Moreover, I wanted to take a grown, that is, more. For a long time, they were chosen, and as a result, they went into boots not the size. When they came home, I found that the boots are not what will increase, and they are already almost small - the big finger on the leg has already resumed into the nasal part of the boot.
It's a shame, annoying, and okay. For a long time I did not burn and found this way out. I took ordinary pliers, wound on the clamping part the ordinary rag moistened in the water, and inserted into the boot. You need to insert so that the leather boots went on stretching, that is, with an effort. Instead of pliers, you can take a suitable hard object that will be approached for stretching shoes to the required size. Now we take the usual iron with a steamer, heating it. On the nasal part of the boot, put a folded halve of cotton fabric and begin to disappear, but only carefully and without fanaticism.
Further leave boots per day. I can say that after all the manipulations made by me, the boots stretched out. Now the thumb of my daughter's leg does not rest, but comfortably and freely fits in the shoes. Hope you use my experience!
A source