what you should do is ride the brakes until you nearly stop then shift to neutral.
however, this is what I do, just in case I might need to engine brake as well.
As I am braking, I wait until I'm about 20-30 feet away (you have to judge), I push the clutch in, down shift to one lower gear while holding in the clutch still, and if I need to engine brake within that 1-2 seconds, I release the clutch slowly. If not, then I just keep the clutch in and take it out of the lower gear into neutral, and then release the clutch.
Keep in mind that this is all done within 2-3 seconds amount of time for you to decide whether you need to engine brake or not. I keep this as a habit only because you might never know when you need to engine brake or not.