If your printouts contain misaligned vertical lines, or you see light or dark horizontal banding, you may need to align the print head.
1.Turn on the printer.
2.Load several sheets of EPSON Photo Quality Ink Jet paper.
3.Windows: 
printer icon on your taskbar (in the lower right corner of your screen) and select Print Head Alignment.
Macintosh OS 8.6 to 9.x: Choose File > Page Setup or Print. Click the
Utility button, then click the 
Print Head Alignment button.
Macintosh OS X: Open the Applications folder and select EPSON Printer Utility. Select SP 960 in the printer list, click OK, and select Print Head Alignment.
4.Follow the instructions on the screen to print a test page. You see this window:
5.On the test page, select the pattern with the two vertical lines most precisely printed on top of each other. You may need to use a magnifying glass or loupe.
Select one pattern each for rows 1 through 4. Enter the number of the best pattern for each row in the corresponding boxes on the screen. Then click Next.
If you can’t find an aligned pattern, choose the one that’s closest to being aligned. Then click Realignment to print another test page and repeat this step.
Maintaining Your Printer 63