Brother MFC-3420C - Manual (Page 45)

2 - 8 LOADING ORIGINALS AND PAPER
How to load paper and envelopes
To load paper or other media
1
Fan the stack of paper well to avoid paper jams and mis-feeds.
2
P ress and slide the paper guide to fit the paper width.
3
Gently insert the paper.
Make sure the print side is towards you and the paper is below
the maximum paper mark.
Paper Guide
Paper
Print Side
Maximum Paper Mark