Backing up your site (GUI)

Backup your Drupal files
Using your FTP client, download all your existing Drupal files to your hard drive and put the files in a folder called 'backup'.

Backup your database with phpMyAdmin

• Select your database from the dropdown box on the left
  If you are upgrading a test site, choose your test site database.
• Click the "Export" tab
• Click "select all"
• Make sure to check the "structure" and "data" checkboxes
• Check "Save as File" desktop
• Click the "Go" button and save the .sql file to your desktop. Let's put it in the same 'backup' folder where you backed up your Drupal files.

This page is much a much more verbose/detailed how-to:

• http://drupal.org/node/120627

And it links to this visual phpMyAdmin how-to:

• http://codex.wordpress.org/Backing_Up_Your_Database