Without seeing the tutorial, I’m going to assume that the slider is a floating point value. If it is not and say it’s an integer value, change the float I am about to tell you to whatever it may be.
Look at your image. Next to the “Name” parameter, just to the right of where you can call the object anything you want, you will see a cog wheel (gear). Click this and choose “Edit Parameter Interface”.
The following window will be divided into 3 sections. On the left the “Create Parameters”. In the middle “Existing Parameters” and on the right “Parameter Description”. In the Existing parameters you will see all the folders are expanded showing all the parameters available. These are the parameters that already exist on your node. Collapse the folders by hitting the little minus next to them. This step is not important, but it will stop showing you all those parameters and make things less confusing to look at.
On the left side “Create Parameters”, you will see a parameter just over 1/4 of the way down called “Float” (0.6). Click and hold, then drag it onto the “root” label in the Existing Parameters section.
Now if you click Apply, you will see at the very bottom of the node, you will see a new slider called “Label”.
Back in the edit parameters window with the “Label” parameter selected in the Existing Parameters section, you can now change the name on the right side under Parameter Description. Name is the actual parameter name that you can reference anywhere inside Houdini, so make this simple but to the point. For example if I was using this slider to rotate a sphere around the Y axis, I would call it something like “sphereroty”. Next is the Label. This is what you will see in the parameter window so in my example I would call it: “Sphere Rotation Around Y” or something alike.
After that hit accept.
Next find the animation that your video has attached to the slider, right click in that animated parameter and choose copy (which is now called a channel due to the animation), then go to your new slider, right click in the sliders parameter and paste relative reference.
If all the tutorial guy is doing is driving a channel with the animation of another channel, then this is pretty much it.
If you still are stuck, link me the tutorial and I’ll see what he is actually doing at that time.