Some sorts of footwear will definitely make plantar fasciitis worse. The two attributes are primarily flatness and a long way second, hardness. Shoes that are dead flat such as thongs, ballet flats, slippers, men’s fashion shoes that look like ten pin bowling shoes, soccer boots (and no shoes at all) are the worst possible footwear to choose. If you examine your footwear and subtract the thickness of the shoe at the ball of the foot from the thickness under the heel, you want the heel to be thicker by about the breadth of your thumb. This will help a lot just by itself. You would prefer then to pick a shoe with sole material with some bounce to it.
Many people do not like to wear shoes in the house but if you suffer from plantar fasciitis, you really have very little choice. Additionally, you are very likely to end up needing orthotics in your shoes – including your house shoes. If you are in a hot climate, consider buying a pair of CrocsÔ shoes as these will still be of use if you end up with orthotics.