Step 1 Downloading Required Files:
Download the files that you require from above
Step 2 Finding the Minecraft Folder:
To get into the minecraft folder go to your startup menu and search up %appdata% (For Windows xp and lower you need to go to run and search up %appdata%) From here you can click the .Minecraft folder. I suggest using a fresh install of minecraft but you do not have to. (You need to delete everything in the versions folder to get a fresh install)
Step 3 Forge:
Run the forge installed and select “Client” from the options.
Step 4 Installing Optifine:
Open up the Optifine winrar file. Copy the whole contents from the optifine file to the minecraft.jar (Located in .minecraft/bin)
Step 5 Launching Minecract:
Next you need to launch minecraft, Once you have done this you need to add a new profile.
Profile name: Anything you want
Use Version: release 1.6.2-Forge9
Attention! TICK JVM ARGUMENTS
Paste the below code into the JVM Arguments (-Xmx1g means you are assigning 1GB of ram to minecraft you can increase or decrease this number)