EdX can not send individual printed copies of certificates. However you can print out your certificate using the printer icon in the upper right when viewing your certificate:
You can also download the certificate to a PDF file using the Chrome or Safari browsers.
Saving your certificate to PDF in Chrome
1. Choose File > Print.
2. Choose Adobe PDF as the printer in the Print dialog box. To customize the Adobe PDF printer setting, click the Properties (or Preferences) button.
3. Click Print. Type a name for your file, and click Save.
Saving your certificate to PDF in Safari
1. Choose File > Export to PDF
2. Type the name for your file and optionally select the location of the file under Where.
3. Click Save.