Pedal and crank -?

what is the best way to fix your bicycle with just one hand?

Erm, I am from England and I don't get it. Suppose it depends what's wrong with it.

with great difficulty
use a screw driver
I'd use a sherman tank myself!
try using your feet as well
simple, carry it home and then get someone else to fix it for you.
You're a very naughty boy....I'll fix your little red wagon all right!