How do I print on A4 paper?

Select A4 in the CHOOSE YOUR PAGE SIZE dialog box before clicking the print button.

Change the Paper Size from US letter to A4 in your printer settings box if it is not the default setting.

If you choose to "try a different print method" during printing, the print option will default to 8.5x11.  You will have the option to change the print size if you select NO, PRINT AGAIN.