Brother MFC-J491DW Online User's Manual page 38

5. Gently press and slide the paper width guides (1) and the paper length guide (2) to fit the paper size.
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6. Fan the stack of paper well to avoid paper jams and misfeeds.
Always make sure the paper is not curled or wrinkled.
7. Gently load paper in the paper tray with the printing surface face down.
Make sure the paper is flat in the tray and the paper length guide (1) touches the edges of the paper.
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