Mongolians are very tolerant people and most will not be offended by foreigners who are unfamiliar with their customs. You will not be expected to know all the traditions of the Mongols, but hosts will be very appreciative to anyone trying to acknowledge Mongolian customs and traditions, especially by foreigners. As the famous Mongolian proverb says "If you drink water from the land then you must follow the custom".
Here are a few "rules" to follow when staying in a ger: