Verbs are conjugated by putting certain syllables (subject concords) in front of them that correspond to the associated noun.
Easiest way to get an impression: Lookup a Zulu verb in the dictionary and then click on "inflect". You'll get a whole lot of conjugation tables for various tenses ordered by persons and noun classes (you might also want to have the subject concords tables of the grammar page at hand). Also try verbs that begin with a vowel to see the changes in the subject concords.
Try to figure out the rules, then come back.

Don't worry, isiZulu grammar is pretty straightforward.