Recommended Version: 1.14.4 (works on any version between 1.13 and 1.14.4, but results might be different)
For Minecraft 1.14.4 you need
OptiFine 1.14.4 HD U F3
Usually, just use the latest version for the Minecraft version you are using.
Allocate more RAM
Really important, increase the RAM allocated to Minecraft to about 5GB (really depends on the map, settings, version you are using etc.)
On the image on the right, you can see how to do this.
This pack is optimised for the Shader "SEUS PTGI" (It is not meant to be played without it)
Make sure to use the latest Shader Version (At the time of writing this: Version E8)
When a new shader update drops, I try to always make the textures compatible as fast as possible.
Other VERY Important Settings: