Find The Right Size
When buying shoes online, you should know your shoe size and always choose a pair in your true size. The size you usually wear. Check your country shoe size. For instance I live in Australia and my size is 9.5. In US this would be a size 11 and European size 41.
Find Discount or Inexpensive Shoes
There are sites that have special partnerships with designer houses and only offer end of season or discounted items so they offer such designer names at far lower prices than you would expect to pay at a boutique or mall store. But be careful in fake or replica items. It is unrealistic to expect to get yourself a pair of branded shoes and only pay $20 for them. So you make sure you are buying shoes online with a reputable store that will ensure you get what you are paying for and not some fake or replica item that will only be very poor quality.
Recognize Poor Quality Shoes
Have Assurance of Returns / Shipping Policy
Remember, you are buying shoes online, not in a boutique so the most important is returning / shipping policy. Reputable online stores offer excellent customer service and make great effort to ensure their customers are happy. When your new shoes arrive, you should try them on to see if they fit correctly. If not, then you will be able to return them for another size or your money back. You should try to find the same shoe in a different size. So always check the return policy before actually paying for your shoes. If an online store does not allow for exchanges, then you should shop elsewhere. They also give you fast delivery (your shoes should arrive within a few days to a week) and a free or inexpensive return service.