Run, making a small footmark (6)
I believe the answer is:
sprint
'run' is the definition.
(sprinting is a kind of running)
'a small footmark' is the wordplay.
'a small' becomes 's' (abbreviation - e.g. clothes size).
'footmark' becomes 'print' ('print' can be a synonym of 'footmark').
's'+'print'='SPRINT'
'making' is the link.
(Other definitions for sprint that I've seen before include "Run at full speed for a short distance" , "To make fast progress" , "Rush" , "Quick dash" , "quick run" .)