How do you conjugate the conditional tense?

You take the future stem of the verb, for -er and -ir verbs, this is the infinitive and for -re verbs, you take the e off the infinitive, and then you add the imperfect endings, -ais, -ais, -ait, -ions, -iez, -aient. There are of course exceptions but it is only the stem which is affected and the irregular stem is the same as the future.