To "make waves" is the opposite of "going with the flow." To make waves is to stand out, to demonstrate your individuality and uniqueness, and to make a name for yourself by becoming better known. Hopefully, when we make waves, it is in a good way, so that we are known for our successes, and not for our failures.
Example: "Martha made waves when she campaigned for extra sick leave for all employees. Not everyone agreed with her, but everyone respected that she genuniely believes in her idea."
Go With The Flow
Figuratively speaking, "the flow" is the course of events; it is the direction society is taking, and the momentum behind the movement in that direction. To go with the flow is to do as others do and to take the path of least resistance, like water coursing through a river.
Example: "You're new on the job. You should go with the flow for a little while until you get the feel of things. You can make a name for yourself later." The new worker is being advised to take his time and not focus on standing out as an individual until he understands the "flow" of the workplace.
Down to Earth
Someone who is "down to earth" is someone in touch with the lives and realities of ordinary people. No matter how high a person's social status, if we say that person is "down to earth," that person does not behave in a way that is separate from the average person.
Example: "Louse makes a lot of money, but she's very down to earth. She treats everyone like they're important and doesn't act arrogant or spoiled whatsoever." This phrasing is meant as a compliment.
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