I'm not sure what you mean by the equation. Zero times anything is zero. Zero divided by anything not zero is zero. This is zero, no particular method required.
If we really need a method, we can treat this either as
[tex]\dfrac{0}{4} \times \dfrac{1}{8} = 0 \times \dfrac 1 8 = 0[/tex]
or
[tex]\dfrac{0}{4} \times \dfrac{1}{8} = \dfrac{0 \times 1}{4 \times 8} = \dfrac{0}{32} = 0[/tex]
