A step by step guide is included in the downloaded package that shows how to install Super Color Ramp (with adequate screenshots).

Once you install and enable Super Color Ramp, it won't be visible in the node group immediately. You need to re-open the current blend file OR open any other blend file or a new project OR you can restart Blender. Now you should be able to see the node in the Shader Editor as well as in the Geometry Node editor under Add>Group menu.

Please watch our video tutorial on YouTube to understand how Super Color Ramp works. It has the similar functionality as that of Color Ramp, but it has added functionality. It allows us to connect other nodes into the input sockets in order to create a dynamic node tree, which is not possible with the traditional Color Ramp node, so we created this Super Color Ramp.

The node has a slight change in its name in the Shader Editor and in the Geometry Node Editor. It is called Super Color Node in the Shader Editor and Super-Color-Node in the Geometry Node Editor. Since Blender does not support the same name in two places for a custom node group, we had to use slightly different names for the two places. But their functionalities remain the same for both the nodes, no difference in that.

Note: Super Color Ramp has one difference with Color Ramp, which is intentional. The input FAC value in Color Ramp is auto-clamped within 0-1 range and you cannot change this. Any value below 0 will be taken as 0, and any value higher than 1 will be changed to 1. But we have changed this in Super Color Ramp. You can pass any value to FAC although it is best to keep it within 0-1 range for most of the cases. Nonetheless, if you have a requirement to use values outside this range, you can do that. If you want to clamp the values within 0-1 range, you can always use a Clamp node just before this node.