First you need to login to your webmail account. To do this go to your webmail.domainname.com address. If you are unaware what to use for the domain name then use this link: (http://webmail.netconsvc.com)
Next type your username and password in. Your username is the first half of your email address and does not include the @ sign.
Then you will click on the icon that looks like a face. Select options from the dropdown menu.
Finally you will click change password on the options window that opens.