If you are looking to get the best performance, here are some key takeaways from the community:
You might need to click "Preview Versions" on the official OptiFine download page to find the 1.19.1 release. Thanks for downloading Optifine 1.19.1
Simply download, run the JAR file with Java, and click "Install". Make sure your Minecraft launcher is closed first. If you are looking to get the best
Glad I could help you get set up with OptiFine 1.19.1! It makes a massive difference for performance and shaders in Minecraft. Glad I could help you get set up with OptiFine 1
To use it with Forge, just drop the downloaded file into your /mods folder.
If you're looking for even higher performance (FPS) on 1.19.1, consider looking into Fabric with Sodium and Lithium. If you run into issues, let me know: Are you using Forge or a vanilla installation ? Did you get a Java error ? I can provide the specific steps to fix it. How to Download & Install Optifine in Minecraft 1.19.1