Changing background colors was discussed under Adding backgrounds. Here I will tell you how to change the color of text, this is very simple. You just add this to the code:

<font face="Arial" color="yellow">Hi</font>

The bold text above would make Hi turn yellow. Of course you would not want to make your text yellow unless you had a background that would make it easy to read. Do not make your site look like a rainbow, make it easy to read and appealing to the eye (Remember that white space is always good).

When choosing colors for your web page make sure they are not crazy. Which means everything should be pleasant to the eye and easy to read. As an example, you don't want to use a white background with bright yellow text because nobody will be able to read it. You also don't want to use picture backgrounds that are complex (ie. a picture of michael jordan dunking tiled). If you are not sure, just show your page to a couple friends and ask them if they find it easy to read.