I'll point you back to my post and bring up it depends how much money and time matter to you, and just how bad is your situation.
You can start with just $40-$50 and get a pair of good insoles like the Sole brand I pointed you to, and the exercises others pointed to.
Or if you're planning to go to a specialist, this is like a nuclear option and be prepared when what they tell you need to do is spend another $500. They may say stuff like we can give you a cortisone shot today and mold a custom orthotic to fix you up. If they bring that up, are you willing to say "yes take my money, give me the shot." If you;re going to balk at the cost and decline anyway, perhaps you're already stuck in DIY land. Only you can say how bad things are..
A simile in cars is if some guy who has a car problem, it seems most the responders here would be like go to the stealership, get it done right, no other options stop trying to save $ to fix it yourself.
Yes your body health is different and should be treated differently, but not that different that there is only one answer.