There are several synonyms for the phrase "plotting a course" that can be used to convey the same meaning. Some of these include "navigating," "charting a course," "mapping out a route," "plotting a path," "setting a direction," and "establishing a plan." Each of these phrases implies a similar sense of purposeful direction and deliberate action. Whether you are using a map or relying on your own knowledge and experience, plotting a course can require a great deal of concentration and attention to detail. Ultimately, choosing the right synonym for "plotting a course" depends on the context in which it is being used, as well as the tone and style that you hope to convey.