Dell 1815dn - All-in-one Laser Printer Owner's Manual page 44

To use the bypass tray:
Open the bypass tray and unfold the paper support extension, as shown.
1
If you are using paper, flex or fan the edge of the paper stack to separate the pages before loading.
2
For transparencies, hold them by the edges and avoid touching the print side. Oils from your fingers
can cause print quality problems.
Load the print material with the side to be printed on facing up.
3
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Loading Print Media