To take the shoes to the store you should have proper footwear, it must be clean and dry, original packaging (not always necessary), cash or sales receipt, which specifies product name, quantity, value, bill of sale is also a signature of the seller.
You have every right to take the shoes back to the store, even if you are missing the factory packaging, or lost cheque (in store should be a duplicate check, the main thing is to remember the date of purchase if the shoes have lost form or has signs of wear. Keep this in mind and do not allow to violate their rights.
You can return the product or exchange it for the same no statement, on the day of purchase. You can also hand over the goods without giving reasons within 14 days after purchase, with no visible signs of use. For example, at home you realized that the shoes don't fit to the wardrobe, rubbing, shaking, or even just not like it, but "walk" you have not yet. In all other cases upon delivery of the shoes back to the store, you want to write a statement about the refund and indicate the reason.
After that, the shoes are sent for examination. Examination may be conducted at the expense of the store. If it is determined that the shoes worn by your fault, you pay for it you'll have. If they admit manufacturing defect, the store will return the money for poor quality shoes and take on all the costs of the examination. Be sure to ask for a written expert opinion, do not trust oral opinion.
If you are not satisfied with the decision, you can challenge it by sending footwear to independent examination. In this case, it will be at your expense, but if she recognizes manufacturing defects, the store will cover your costs. This will also need a copy of the opinion of a specialist. Don't be afraid to attend the examination in person or record it on camera. This can be an additional advantage if the store violated your rights and you will have to go to court.
You can take the shoes to the store within two years after purchase, provided that it does not show any mechanical damage due to careless operation.