The you form of a verb is used to express intention, such as let's do something or I'll do something. To convert ichidan verbs (end in the sound eru or iru) into this form you remove ru (る) and add you (よう).
Taberu (to eat) becomes tabeyou (食べよう)
You must change all godan verbs so that they end in the sound ou. Godan verbs that end in u (う), you remove u (う) and add ou (おう). For all other godan verbs you change the last syllable (which ends in a kana with the u sound) and change it so it ends in a o sound and then add u.
Iku (to go) becomes ikou (行こう)
Lets read kims book = kimu-san no hon o yomou
The irregular verbs forms are shiyou (しよう) and koyou (来よう).
Let's get married = kekkon shiyou (結婚しよう)
To use the form of verb in the polite form you use the ending mashou (ましょう). Attach this word to the end of the masu stem. If you do not know how to create the masu stem go here
Let's go = ikimashou (行きましょう)
Let's drink beer = biiru o nomimashou (ビールを飲みましょう)