Mods/Installing Forge mods

Minecraft version 1.6 and Later (Cross-platform)

 * 1) Go to files.minecraftforge.net
 * 2) Find the latest or recommended build for your version of Minecraft (must be +1.6).  The download links are next to the build and Minecraft version, download the one called 'Installer'
 * 3) Once it has downloaded, either run it (Windows) or double-click it in the 'Downloads' list/folder (OS X and Windows).  Linux users get to run the JAR file manually, with a command such as
 * 4) This will open a window called 'SimpleInstaller' there will be a ticked box saying 'Install Client,' keep it ticked
 * 5) (Optional) If you want to choose a different install directory, click on the '...' button next to the box saying the file path of the default install directory (.minecraft folder) then just simply select the folder you want to install into
 * 6) Click install and wait for it to finish
 * 7) Open the new MinecraftLauncher and either select the profile 'Forge' or click 'Edit Profile' and change the version 'release x.x.x-Forgex.xx.x.xxx' ('x' means that it could be any build, e.g. 1.6.4-Forge9.11.0.884)

Single player Minecraft before version 1.6
This is for installing Forge API on old versions of minecraft. It is now out of date as 1.6 allows for a Minecraft Forge "SimpleInstaller"

Steps:

Windows

 * 1) First of all, you need to 'Force Update' Your game to remove any mods installed otherwise we may encounter issues during installation of Forge. You can find the 'Force Update' button by clicking on the 'Options' button on the minecraft launcher. After selecting force update, login and all the files minecraft requires to operate will be redownloaded and installed on your computer.
 * 2) We now need to download Minecraft Forge, The link will be at the bottom of this post
 * 3) Once Minecraft Forge has downloaded open it with WinRar. (Or a similar program such as 7Zip)
 * 4) You need to close your minecraft after it has force updated
 * 5) You can get to your .minecraft by clicking the 'Start' button and typing in your search bar '%appdata%' then clicking roaming then clicking .minecraft. For XP users you would use 'run' instead of search.
 * 6) Open the 'bin' folder and open the Minecraft.jar with WinRar. (Or a similar program such as 7Zip)
 * 7) Delete the META-INF folder in the minecraft.jar
 * 8) Right click anywhere in the Minecraft Forge Zip and select 'Select All' or press  +  and drag all the files from the Minecraft Forge Zip into the Minecraft.jar. Do not delete the Forge META-INF!
 * 9) After moving all the forge files into the Minecraft jar close both ZIP files.
 * 10) Lets run minecraft to see if we installed it correctly.
 * 11) If you see a button called 'mods' on your menu then Forge has been installed correctly.
 * 12) To install forge compatiable mods please follow the mods installation instructions.

Mac
1. Don't forget to Force Update! Close it thereafter.

2. Go into your Library via the Finder app and enter the Application Support folder.

3. After you find the folder "minecraft", go into the bin folder and extract minecraft.jar with the app The Unarchiver.

4. Install the version of Forge, it should extract on its own. It will contain several classes.

5. Place the new classes in the extracted folder one by one. You can also delete META-INF if you wish (it is recommended). Don't forget to remove the materials from the ibxm folder as well!

6. Test Minecraft, and if a menu pops up, you've successfully installed Forge!

7. Add any mods that you wish in the mods folder in the finder (or the coremods folder if it is a coremod), and enjoy!

Download Links:
Minecraft Forge 1.4.2: http://files.minecraftforge.net/minecraftforge-universal-6.0.1.341.zip

Minecraft Forge 1.4.4: http://files.minecraftforge.net/minecraftforge-universal-6.3.0.372.zip

Minecraft Forge 1.4.5: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.4.5-6.4.1.436.zip

Minecraft Forge 1.4.6: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.4.6-6.5.0.467.zip

Minecraft Forge 1.4.7: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.4.7-6.6.0.497.zip

Minecraft Forge 1.5: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.5-7.7.0.582.zip

Minecraft Forge 1.5.1: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.5.1-7.7.2.678.zip

Minecraft Forge 1.5.2: http://files.minecraftforge.net/minecraftforge/minecraftforge-universal-1.5.2-7.8.0.684.zip

Older Versions: http://www.minecraftforge.net/forum/index.php/topic,5.0.html