venous insufficency-how (elevated) to prop leg?

I have venous insufficieny in my left leg. It is very swollen.
I am told to keep my legs propped up.....but how high?

Should my hassock be the same height as the seat of my chair.
Should my ottoman be a little higher or a liittle lower than the seat of my chair?

Should my ankles be above my heart?

Thanks

[LeslieK55]

I have been told to keep fee elevated above your heart with most heat/heating pad.