Determine how to nondimensionalize the mass on a spring equation so that the dimensionless equation takes the form

$$\displaystyle{\alpha \frac{d^2X}{d\tau^2} + \frac{dX}{d\tau} + X = \cos{\beta \tau}}$$.

What are the definitions of $$\tau$$, $$X$$, $$\alpha$$, and $$\beta$$?