Friends Overlay adds a friend system to minecraft it is one of the best mods I have seen and I have been modding sense 1.4

Step 1: Forge

If you haven't already install forge you can get it from files.minecraftforge.net download the installer then install it. Then turn minecraft back on with the file "forge"

Step 2: Download

Google "minecraft [version] friends overlay mod" try to get it from 9minecraft it is a very trustworthy site.
The site it redirects you to is not an ad the download button will download the mod but there will be a tab or window for an ad just close it

Step 3: Install

Use "run" to search %appdata% click"roaming" then ".minecraft" then "mods" place the friends overlay file that you downloaded in that folder as if you were installing any other mod

Step 4: Register

Register for an account at friendsoverlay.com

Step 5: Sign In

When you start minecraft there should be a button to the right of the quit button that says "FO" click that and sign into the account you made on friendsoverlay.com

Step 6: Finished

Now get friends to sign up for the mod
-you can get servers from them
-know when they are online
-know what server they are on or if they are playing single player
-you can also chat with them
if you want to you can send me a friend request my user is kdbarnes
There is more info about the mod on the website you downloaded it from