My friend's doctor told her to help get blood to feet and ankles, anywhere she is, rock toes then heels, back and forth. Following day, I noticed an article online that mentioned similar: rolling feet and ankles in circles. Also mentioned was: in rocking chair with feet planted on floor, rock and keep feet on floor.
Just ideas for those of us who sit too long, or have problems with swelling legs, ankles, feet. (Me, both.)