Samsung SF-555P - Manual (Page 98)

4.5 Printing
4. Slide both paper adjusters to fit against the paper’s edges. Ensure
the paper line flat in the tray.
Print Side Up
Most papers prints better on one side than on the other. This is
especially true for coated or specially treated paper. The print side is
usually indicated on the paper package. Be sure to insert the paper into
the paper tray of the printer with the print side up.
Using the Manual Paper Input Tray
To load a single envelope, card stock, or specialty paper, use the manual
paper input tray. When you use the manual input tray, you must feed
one piece of media at a time. Manual feeding is helpful when printing on
heavy paper or when experiencing paper jam with the automatic paper
input tray.
Manual paper
input tray