How do I send a fax using the Fax Utility in Windows?

See below.

Sending Faxes Using the Fax Utility - Windows

You can send a fax from a printing program in Windows. You can fax up to 100 pages at a time, including a cover sheet.
1. Open the file you want to fax and select the print command. You see a window like this:
   
   
2. Select your product with the FAX option as the printer.
3. To change the Paper Size, Orientation, Color, Image Quality, or Character Density settings, click the Preferences or Properties button.

   Note: If you see a Setup, Printer, or Options button, click it. Then click Preferences or Properties on the next screen. For more information about selecting fax print settings, click Help.

4. Select the Page Range as necessary. (Leave the Number of copies set to 1.)
5. Click Print or OK. If you’re faxing for the first time, you see a window like this one:
   
   
6. Enter your sender information so that recipients can identify the origin of the fax. Then click OK to save the sender information. You see a window like this:
   
   
7. Enter the recipient's name and fax number or select a recipient from the phonebook, then click Next.

   Note: For detailed instructions on using the Epson FAX Utility, click Help.

8. Select a cover sheet and enter a subject and message, then click Next.
9. Click Send to transmit your fax.