HP LaserJet Pro M435 Multifunction Printer series - Manual (Page 23)

5. Load the paper into the tray. Make sure that the
paper fits under the tabs and below the
maximum-height indicators.
The way you should orient the paper in the tray
varies depending on the paper size. For
additional information, see Tray 1 paper
orientation on page 16 .
6. Adjust the paper guides so that they lightly touch
the paper stack but do not bend the paper.
NOTE: To avoid jams, do not add paper to Tray 1 while the product is printing. Do not close Tray 1 while the
product is printing.
ENWW Load Tray 1 (multipurpose tray) 15