I've never heard someone say follow the money. The only reason I can think of is if you were trying to start a business, a mentor might say to you 'follow the money' - i.e create your business around something there is a high demand for, so lots of people will be wanting to pay for it.
Think for yourself - my father said that for me lots of times when I was a teenager! That means, when you are presented with a decision or even a thought concept, rather than going along with what your friends and family think and do, you use your own knowledge and sense of right and wrong to make the decision. But note this doesn't always mean you will develop different ideas to them. An example might be, you are at a part and someone starts passing around hash cookies. Everyone is telling you to eat one because they'll make you feel great, and they are all eating too. You could do one of three things: eat one without thinking about it, or you could think about it - you might be suspicious about the effects of eating marijuana, or how it effects your medications, or maybe you had one before andit was really gross, so you decline. Or you could think about it and decide, to hell with it, I'll have one and see what all the fuss is about, it's not like I get stoned regularly.
The latter two choices are examples of thinking for yourself, does that make sense?
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