If you are seeing marks of ink (usually black) on the edges or in the middle of the paper the print head is too close to the paper.   

Step 1 : Increase the Paper Suction amount - This will draw the paper down on the platen so that the paper will be further from the head. To do so lift the paper lever up and then hit the up arrow button on the printer.  You will hear the vacuum increase.  Do this in increments until the marks are gone from your print.  

Step 2:  If increasing the vacuum did not work, raise the platen gap.

Go to your printer and hit the right arrow button until you see platen gap, click right again and you will see an asterisk next to the option that is chosen for the media type you have loaded on the printer.   If you are on Narrow, move up to Standard and press the enter button, you will move the asterisk up one level at a time and print until the issue is resolved.