Rosie, resistance = resistivity X length of the wire.  Resistivity is a bit like density but in this case it's resistance over distance.  So naturally resistance R = rho L; where rho is the resistivity in ohms per meter for example.

So since rho is a fixed value we see that the resistance of that wire varies directly as R = rho L with the length of the wire L.  The closer L gets to zero length the closer R gets to zero also.  As short as possible.  ANS.

The thinness is a bit more complex.  Think of a wire to be like a water pipe.  Which pipe, the large one or the small one, would carry the most water?  The large one naturally.  Same sort of deal with a wire.  The bigger (thicker) wire will carry the most free electrons so there is less resistance to them flowing.

As short as possible like plumbing but that analogy is still lacking.