In order to update content on your site, you need to log in to your WordPress dashboard as follows:

Open your FireFox or Internet Explorer browser.
Type in the web address (URL) of your web site in the address bar at the top.

Add /wp-login.php to the end of your web address.

example:
www.yourwebsite.com/wp-login.php

At the WordPress log in screen, enter the username and password that was assigned to you.

You will now be in the Adminstration panel for your site.

Please review the other Client Resource pages for details on how to do basic WordPress tasks via the Administration Panel

For details on all the Adminstration Panel functions, visit http://codex.wordpress.org/Administration_Panels