It depends on what treatment you have had thus far, what your symptoms are and how your symptoms are affecting your activity.
In general most doctors will recommend initial treatment with an ASO brace (easily purchased online).
In addition to the brace you should also pursue physical therapy. This shouldn't require more than a few visits with a physical therapist. They should be able to provide you with the appropriate exercise instructions and equipment (theraband, BAPS board, etc.).
If you have a higher arch foot you may also want to consider a lateralizing heel wedge (again found online) to put in your shoe. This will take some of the tension off of the tendons.
After 8-10 weeks if the pain still persists then your doctor should consider an ultrasound guided steroid injection in to the peroneal tendon sheath. Recent research has shown this can be effective at relieving the pain and is very safe.
With continued symptoms despite all of these treatments that is significantly impacting quality of life, or keeping you from doing necessary or desired activity then your doctor will likely get an MRI to see if you have tendon tearing or other problems with the tendons. If so, reconstructive surgery may be indicated.
Hope it helps!