ETY: Both hands indicated as the feet. The motion of going 'Upanddown-Downandup' in a repetitive manner is considered as an _awkward_ walking motion. Its feet presumably have three digits of toes, thus make it imbalance through walking. Hence the concept of the word, "Awkward" is introduced.
This two-handed ASL sign is produced with a facial expression suggesting awkwardness:
Posture the nondominant hand in the “3” shape about half an arm’s length in front of and beside the chest, nondominant palm facing down. Posture the dominant hand in the “3” shape in front of and beside the trunk, dominant palm facing down.
Move both hands alternatingly and repeatedly up and down.
Posture the nondominant hand in the “3” shape in front of and beside the trunk, nondominant palm facing down. Posture the dominant hand in the “3” shape about half an arm’s length in front of and beside the chest, dominant palm facing down.
(clumsy): A different facial expression expresses the meaning "clumsy", typically with the mouthing "TH".