If you prefer a more practical method of choice, start to look for patterns in your life. Do you find yourself encountering one type of animal on a regular basis? I know a witch who adopted the spider because she had a house full of them and felt they were brought to her for a reason. Are you drawn to the characteristics of a particular animal? Do you identify with self sufficient tortoise,wise owl or independent rat?
Do certain animals turn up in your dreams? Try keeping a notebook by your bed so you can document your dreams. A lot of people find their spirit animals through the dream world.
You will know an animal is your totem or spirit animal when the connection just feels right for you. Once you have established this connection, research the behaviours and characteristics of the animal and see what you can learn from it. What is your spirit animal trying to tell you? How can you adapt your own behaviours to benefit from the wisdom you can learn from the teachings of your chosen animal totem?