How can I make a path for character move along

In my case, I want to make a rolling coaster game. I need to make a path for character walk along with the path. the path maybe a circle or curve or something like that.
how can I draw a path and how can I make my character go fluency

Finally I got the anwser just looking for the spline tool tutorial or matinee tutorial.

Hi can you upload a sample file or a detailed blueprint screenshot ? I have been following some tutorials but for some reason its not working. Can you let me know which tutorial you used for the spline following ?