Wear them
You don't need to break in ballet flats, but you do need to break in pointe shoes.
When your other shoes break or you need new ones:).
If your brake shoes are squeaking you need to take it to the nearest expert technician or mechanic which will tell you how to change your shoes and if you need to.
because when you are about to jump and you don't wear the right kind of shoes you can break your calves
break lining break pads break shoes break pipes break fluid leakes brake disk
I find that the VERY BEST way to break in hard shoes is to wear them around the house ( a lot! ) and to dance in them. I tried Vaseline, but it didn't help.
You install break shoes using the instructions listed on the package the break shoes come in. They are simple and easy to follow. If you need more help, contact your local auto repair shop and I'm sure they would be happy to assist. Most shops only charge small fee.
Not for regular ballet but for pointe there is a chance that you could break toes.
to "break them in" or mold them to their foot more easily
Easiest way is to play around on a skateboard in your driveway or to wear them everyday for about a week.
Bloch sylphide are very good, not too strong and good for a beginner's foot that is not too strong. Very easy to break in. other types of bloch shoes can be more difficult to break in.