How to make money in Poe?

I found that an easy way to create chaos orb was to sell a single division card that dropped during the game. Maybe I’m the only one, but in an ordinary 3Mo League, I’ve never completed a full set of expensive div cards. For example, I sold the following div cards the other day:
Mayor – 40 chaos. Pride Pride before the fall – 35 chaos.
I doubt if I’ve ever played these games, and I don’t intend to “farm” them.
Easy 75 chaos.
Editor: basically, take a look at your div card collection and find out that there is only one card and more than 5 cards are needed for the complete set. Check the price on poe.trade and sell it for more than 10 chaos.

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