I've got peroneal tendinitis in both ankles, most severely in the left. While not exact to your condition, what I have done as far as treatment may help you a bit. When either ankle flares up ill wear a brace for a few days during activity.
On top of that your run of the mill RICE therapy, when resting, will help bring down some of the inflammation. I've also made a more conscious effort to include ankle mobility and strengthening work and have seen a decrease in the frequency and severity of the flare ups.