There are many different email packages on the market today. However, they all function pretty much the same.

Start by opening a new eMail. In the eMail window, you should see a button with a paperclip icon. Click this button.

If you don't see the icon, look for a button named something like "Attachments" or if you have a "Message" menu, look in the menu for a "Add Attachment" option.

A standard open dialog should appear. In the open dialog, locate the file you want to attach to the email. Select the file (by clicking it) and click "Open" (or "Select" or "Attach" or "OK").

You should now see the file listed in the eMail as an attachment.