I thought I'd do a similar themed post ready in time for Valentine's Day.
The theme this time being... how you know if he's a keeper:
Amusingly enough I know how this would work the other way round. If men were posed the question "how do you know if she's a keeper?" the answer would blatantly involve sex in some shape or form. *le sigh* Or something along the lines of "she can cook a mean curry / chilli con carne / chicken katsu / lasagne" [delete as appropriate]