How to store note only on my Mac in Notes 4? I'm trying the new Notes.app version 4 with El Capitan. I "upgraded" my existing data to be compatible wit the newly revamped version of this app.

I have an "iCloud" group on the left panel, with a couple folders. But I do not have an "On my Mac" group. 

So how do I store notes only on my Mac rather than through iCloud?
Choose Notes > "On My Mac" Account

I have just opened Notes on El Capitan to verify this. Please click on Notes in the menu bar, then click on "On My Mac" Account to access the local storage facility. The new group will appear upon clicking this option.