Changing colours in the Drupal 5 Garland Theme is trivial for those who have seen a colour picker before but could be baffling to others.

How to change colours on the Garland Theme

1. Click Administer » Site building » Themes.
2. Click the "configure" link in the Garland row
3. You have two choices:
   1. Pick a pre-defined Color set: e.g. "Pink Plastic", "Ash", etc. OR
   2. Change the colours below e.g. "Base color", "Link color:", "Header top:", "Header bottoms:", "Text color:" by either typing a hex colour code OR by clicking in the number beside the colour you want to change and then using the colour picker. The colour picker consists of a rainbow wheel that allows you to select the hue of a color, and a square in the middle that allows you to choose the brightness and saturation. Click and drag on either to change the value of the last selected colour field. You will see the changes reflected below.
4. There also lock icons beside each colour. The lock icons allows you to link colours together and unlink them again. Changing one of a set of locked colors will create a palette for the other colors based on the original scheme.
5. Click "Save configuration"

A picture is worth a thousand words in this case. See below for an explanatory graphic and screencast.

Explanatory Graphic

Screencast

(original 6.1 MB MPEG-4 file, lower quality flash video)