NEW YORK ( TheStreet) -- Earnings are likely to be terrific next week, Jim Cramer advised his "Mad Money" TV show viewers Friday. But even if they are, Cramer still told viewers to use caution and only buy after they've had time to digest the conference calls. He reminded them that the headlines are often wrong when it comes to corporate earnings, and the devil is always in the details. That's why on Monday, Cramer said he'll be listening to the conference call of Citigroup ( C) to see if that beleaguered bank has anything to say in the way of a dividend, a buyback or anything positive for shareholders. If not, look for the entire banking sector to be weak, he said.