Optifine

1. Download JDK (Installer version)

2. Download Latest version of Optifine (click mirror)

Note: mac users will be prompt with a window that says something regarding security. To open the .jar file you must go to System Preferences -> Security and Privacy and under general tab you should see a button that says Open Anyways. Click that.

Windows users click keep upon downloading and install normally.

Minecraft settings for further optimization