have you checked out the tutorials? there is an example for harmonic analyses. also your reseller should offer dynamic analysis training that will cover all the dynamic analysis types. we offer it online if you're interested www.hawkridgesys.com
it might be helpful for you to describe what you're trying to do and what spec you're trying to follow but generally the process is the same as other simulations.
add a fixture
apply load (usualyl base excitation where your curve is a value vs freq)
set your study settings for number of freqs and discreitzation
improve mesh and other variance parameters