Requirements:
- FTP
- able to use .htaccess
- Text Editor

Steps:
1. Create the 404 custom page
2. Find or make .htaccess

Step 1. Create the 404 Custom Page
It is every easy..
Start to create your page that will now be the 404 ERROR Page...
name it what ever you want... I add anything you want.. Now you want to upload it to your site through FTP.

Step 2. Find or make .htaccess
Find in your FTP .htaccess...
If you don't have one do not worry. You can make a new one..
Download and edit your .htaccess file or open Text Editor.
and past this in there: ErrorDocument 404 /404.html
all one line.. "ErrorDocument 404 /404.html" is what you need to add on to the page.. /404.html is linking it to the page on your site so what you name it in step 1 is now where you want to link it...
now save it as .htaccess
If you are in a sub domain do this "ErrorDocument 404 /sub/404.html" Do not add the HTTP link this will make the Error to make it look like it did find the page.... Now upload it to your ftp.. Try it out..

Well That is it...
I hope you find this every easy because it is..
If you are having trouble just email me at drummingguy@fallenanime.com.
I would happy to send you the .htaccess file and you can edit it....
Check out more cool tutorials on my web site Fallenanime.com

FAQ:
Q.What is a 404 ERROR Page?
A. 404 ERROR page is when the bowser can't find a page on your web site. like if you typed "youname.com/hi" and that page was not there that will now be a 404 ERROR..