Is one to avoid drying his feet after Mikveh?[1]
It is proper to leave at least one area of one’s body wet from the Mikveh water in order so the body absorbs the holy water.[2] Based on the above one may let his feet remain wet and dry the remainder of his body in order to fulfill this directive.
[1] Shaareiy Halacha Uminhag 1:131
[2] See Kaf Hachaim 260:5 in name of Arizal that one is to not dry off the Mikvah water on Erev Shabbos. The Rebbe ibid extends this custom as well to the daily immersion.