Lymphedema is a difficult subject for which to find much clinical information on the web, since the most common cause is the removal or damage to lymph glands and vessels attendant to surgical/radiological attacks on cancer - especially of female breasts. Since most search engines, even on academic sites, present results based on "popularity" the reports on post-cancer-treatment treatment drive everything else into oblivion.
There are a number of websites dealing with edema from other causes, but a lot of what's there is imagination rather than information, so caution about what you believe is recomended.
Massage therapies do seem to have some usefulness.
Pressure bandages work fairly well in some cases.
In some cases a diuretic may be prescribed simply to reduce the amount of fluid retained. Excess lymphatic fluid that's the result of an infection may exceed the capacity of the lymphatic circulation system, and excess cellular fluid of any kind can obstruct the lymphatic circulation. Since even the least aggressive diuretics can cause potassium (and probably magnesium) deficiencies you probably should pay attention to both, and a doctor who prescribes a diuretic may want fairly frequent testing to assure that they're not a problem. Many doctors are reluctant to prescribe any diuretics due to a fairly small but common possibility of degraded kidney function with prolonged or excessive use.
Since circulatory problems can cause edema, and edema is a common "symptom" of a heart attack (think "congestive heart failure") if you're being treated for any form of edema your cardiologist (assuming you have one) should be informed of that condition, since otherwise some forms of actual or apparent "heart attacks" may be misdiagnosed and improperly treated (been there, I think).