The pronunciation of "御"

When you go to Japan, or go to Japanese restaurant, you may see a lot of vocabularies with the Kanji "御".
For example, 御飯（Gohan, means meal）, 御風呂（Ofuro, means bathroom）, 御客様（Okyakusama, means customer）, 御神籤/御御籤（Omikuji, means written oracle）, etc.
We can find there are 3 pronunciations of the word "御", which are "Go", "O", "Mi". Then, how to confirm the pronunciations in simple way?
If the vocabulary is as same as Chinese, and pronunciation likes Cantonese, the "御" would be "Go", such as 御家族（Gokazoku, family members of the person who you are communicating with）. If the vocabulary cannot reach both of the 2 conditions above, the "御" would be "O", such as 御電話（Odenwa, means telephone, since "denwa" likes Mandarin but not Cantonese - dinwa, this vocabulary cannot reach the second condition）. If the vocabulary which is related to religious or 天皇（Tennou, Emperor in Japan）, the "御" would be "Mi", such as 神酒/御酒（Miki, means alcoholic beverages which are placed in shrine）.