EXCERPT TROUBLE

Okay, after reading practically every post and the excerpt basics, etc. I am trying to find out what’s going on with my site.

I have some posts that were made a while back and they’re simply to long to be displayed on the main pages. I need to add excerpts, so I went back and added excerpts when I was editing the post area. However, when I go back to the site, nothing’s changed.

I’ve tried pretty much every plug in and the same thing happens… NOTHING. Can someone start from the very beginning and tell me what I am doing wrong?

If I need to edit some .php files with codes, please don’t just tell me the code that needs to be inserted like the “basics for excerpts” post on here… PLEASE PLEASE PLEASE also tell me WHICH php file it’s supposed to go into! 🙂

Thanks!!