Shaders are a beautiful addition to Minecraft that give the game anywhere from a slight lighting boost to a full overhaul of the game's scenery. To use these shaders, you'll need to use either the Optifine Mod or Iris Mod, both of which have their own installers to make getting set up simple and easy.
Shaders do not need to be installed on the server and only need to be installed on individual computers. You can even play vanilla servers with shaders on.
Iris - Download
OR
Optifine - Download
Optional Shaderpack to use:
BSL Shaderpack - Download
1. Run the Iris Installer from the link above.
2. Select your preferred Minecraft version and click Install
3. Open the Minecraft Launcher. You'll now be able to select Iris and Sodium. Launch the game with this selected.
4. Download any shaderpack. You can use the one linked above (BSL). Once downloaded, you'll have a zip file.
5. In Minecraft, open Options → Video Settings → Shader Packs → Open Shader Pack Folder
6. Drag your shaderpack zip file into this folder.
7. In Minecraft, select the shaderpack. The game will now load with beautiful shaders installed.
1. Run the Optifine Installer from the link above (May not have the latest version).
2. Click Install
3. Open the Minecraft Launcher. You'll now be able to select Optifine. Launch the game with this selected.
4. In Minecraft, open Options → Video Settings → Shaders
5. Click Shaders Folder
6. Drag your shaderpack zip into this folder.
7. Select the shader and click Done. The game will now load with shaders.