Teach your students regular verbs first. French verbs all end in -er, -ir or -re. Regular verbs have a specific pattern as to how they are conjugated. Have your students practice conjugating regular verbs in all six of the pronoun categories: je, tu, il/elle/on, nous, vous, and ils/elles. Take for example, the regular verb "parler" which means "to talk":
je parle
tu parles
il/elle/on parle
nous parlons
vous parlez
ils/elles parlent
The stem of the verb is "parl" while the suffix depends upon the pronoun. The same basic endings, e, es, e, ons, ez and ent, apply to all regular verbs.
Teach your students the irregular verbs; they each have their own conjugation, so there is no set pattern for irregular verbs as there is for regular verbs. For example, the irregular verb "dormir" (to sleep) doesn't follow the regular verb conjugation pattern. Instead it is conjugated:
je dors
tu dors
il/elle/on dort
nous dormons
vous dormez
ils/elles dorment
Learning irregular verb conjugation takes memorization and practice; give your students regular exercises to help them learn them.
Teach your students which verbs are conjugated with the verb "etre" (to be) in the past tense. There are sixteen of these verbs. There is a mnemonic device that can be used to help students memorize these verbs: Dr/Mrs. Vandertramp. Each letter represents a verb conjugated with "etre" in the past tense: descendre, rentrer, mourir, retourner, sortir, venir, arriver, naitre, devenir, entrer, revenir, tomber, rester, aller, monter and partir.
Teach your students how to conjugate in the the past tense; there are 13 other tenses they will eventually need to know, but the past tense will be most useful to them when learning the bases. For example, to say that you had eggs for breakfast you would say "j'ai mange les oeufs." Note the the "e" on the end of "mange" should have an accent above it.
Teach mnemonic devices and songs to your students to have them memorize the rules for French verbs. These tools will help them retain what they have learned. Provide daily homework and exercises that have your students practice pronouncing and conjugating verbs.