Steps for you:
-- Install Skype app on iPad.
-- Create account (can't remember whether you can do that on iPad app, but if you can't, go create one on the Skype website ad sign into the iPad app with the same logon and password).
Steps for the other party:
-- Install Skype onto PC.
-- Create an account.
Then either of you can search for the other and request that the other person allow you as a contact. To do that on iPad app, hit the plus sign on the upper right and search. Once you've found the right person and request contact, you wait till he/she accepts. Then you're in business for Skype calls. They'll stay in your contacts list and you just click to call each time, as long as they're signed on.
I'm doing this by memory, so the exact steps might be a bit off, but these should get you going.