I got plantar fasciitis from wearing a 1/2 size too small shoes in the summer when my feet swelled..
My chiro treated mine.. low level laser & arch supports and I got rid of those shoes so I never wore them again.. he also did some foot/ankle stretching & massage. but that laser took the worst of that pain away & the arch supports kept it away..
I got extra arch supports off the shelf at the local department stores, some brands are more comfortable than others , so a store that has easy returns is nice..

Even after the pain faded away I liked the support from the arch supports so still use them in certain shoes, but don't need them now..