Get to the part in your post where you want to have your reader click to see the rest of the post and simply click on the !M button in your toolbar.
it will insert something that looks like <!--more--> which will in place Read more as a link to the rest of your post.

im sorry but i don't see any !M button in my toolbar. where is it located under?

Note the three buttons before the X at the right of this image...

http://wow-factor.com/img/toolbarbuttons.jpg

!M is the one I'm referring to.

If you don't see this toolbar then you have bigger problems than READ MORE :)

The advanced Write section looks something like this in Version 2:

http://www.blog.hemminga.net/B2evoforum/Quicktags.png

If you don't see this bar, goto Global settings -> Plugins install -> install new and install the Quicktags plugin.

Good luck

oh ok i see it now..

thank you everymuch.

For the ones wondering what that second bar in my picture is, it is the [url=http://wonderwinds.com/hackblog.php/2008/01/moretags-plugin]More Tags plugin[/url] by EdB.

Have fun