Totter up gets sly look (4)
I believe the answer is:
leer
'sly look' is the definition.
(I've seen this before)
'totter up' is the wordplay.
'totter' becomes 'reel' (I've seen this before).
'up' shows that the letters should be reversed in order (in down clue: letters go upwards).
'reel' reversed gives 'LEER'.
'gets' is the link.
(Other definitions for leer that I've seen before include "Stare suggestively" , "Lewd look" , "Gaze lasciviously at" , "Look lasciviously at" , "Ogle, smirk" .)