What does a gentile have to do to keep the laws of B’nai Noach? I have been told that there are actually more than the 7 laws. What are they?

The seven Noahide laws are: 1. Idolatry 2. "Blessing" of the divine name 3. Murder 4. Adultery 5. Theft and civil law 6. To establish courts system 7. A prohibition of eating a limb torn from a live animal It is true that there are a few more Mitzvot that non Jews are commanded, for instance the commandment to fulfill the oaths and vows they take open themselves. The commentators bring different reasons to why these sort of commandments are not listed in the Noahide laws; here are some. The Tosfot Avodah Zarah 5b states that only negative commandments were listed. Rav Shlomo Kluger (Nedarim 8) and Mishneh LaMelech (Melachim 10; 7) say that they stem from the initial seven. The Avnei Nezer (YD 306) writes that all commandments that are reasonable and logical to mankind – are applicable to all mankind.