Maximise Q factor in low pass Sallen and Key Filter

How do I maximise the Q-factor of the low pass sallen and key design.

I have this equation: $Q = \sqrt{ \frac {(R1 \times R2 \times C1 \times C2)} {R1 \times C1 \times (1-A) + (R1 \times C2) + (R2 \times C2)}}$

but I'm not sure of the best way to maximise it!

-