Hello, how can i creat an effect similar to the confusion when u eat a puffer fish in 1.8

So i only want to change how the picture that is renderd for the screen and not anything in game

Thanks in advance

What you're looking for is a Shader.

There are that supersecret settings from vanilla, can i use the shaders from that without the:

   		 Minecraft.getMinecraft().entityRenderer.activateNextShader();

?

So the player cant just turn em off again?

Are there any good tutorials for shaders?

You need to write your own shader.

 

As for tutorials on shaders: yes, but you're not going to find them for Minecraft, because shader code is independent from Java.  As in, divorced entirely.  I'd link you to one (Unity's got some good resources) but I don't know what kind of shader you need to use (fragment, vertex, etc.)