A power animal is an aspect of self that is represented by an animal. The aspects of that animal apsect can be empowered and encouraged such that it assists you in your life. A power animal is not a separate spiritual being that happens to live within your underworld soul. Personally, I like the idea that I am the only one in me. Assistance can be offered to those who have more than one spirit living inside them.
A plant either of the genus salvia (sage) or artemesia (sage brush). White sage is salvia and is typically used for cleansing. Artemesia sage is often used in a sweat lodge for calling up one's spirit. Artemesia is often prepared as a sage stick for smudging.
A totem is a guardian or guide for a group
of people, be that group a family, clan or tribe. For example, the totem for the Ute people is Bear. They hold an annual ceremony to reflect that relationship. You might wish to think totem pole. A totem pole, which may have various totems on it, serves a group, not an individual. Many people misuse the word totem, but it is very well defined and some other word should be used when meaning a guide or guardian for an individual. Otherwise, we will have to think up a new word to use when we actually do mean totem.