I really do not get this stuff about predicate nominatives so how do you do this? Teach me to the point that I understand it!

A predicate nominative is a noun following an equals verb that is identical to the subject noun.

Simple example
Boy is brother. Boy = brother.

Equals verbs are any form of the verb to be. ( am, is, are, was, were, be, being, been )

Dogs were Shelties. Dogs (noun subject) = Shelties ( predicate noun)

http://grammar.uoregon.edu/nouns/predicateN.html