Start by following the basic process for fraction multiplication, turning any mixed fractions into improper ones. Before you cross cancel or multiply, however, swap the numerator and the denominator in the second fraction. This is called taking the reciprocal and it is the key step to turn this into a division operation. Then, cross cancel, multiply across to get the answer fraction, and reduce.
When you see a fraction, you see a numerator and a denominator. To find the common factor, see whichever number among these is least: The numerator, the denominator or the difference between numerator and denominator.