EXAMPLE:
 
   
1. Go to THIS site, copy the code. Go to Customize > Edit HTML and paste the code BEFORE the </head> tag (use CTRL+F to find it). If it doesn’t work, try putting the code before the </body> tag. 

2. Changing the color: if you want it to be colorful, you don’t need to change anything. But if you want just one color, replace “random” with color you want. Remember: it must be a HTML color (examples: black - #00000, blue - #0000ff).