Agree re the spelling tho' strangely, quite a few people seem to pronounce it as if it had a u in it!
Agree that to make it with half the quantity of coffee, you'd just use half the quantity of water (or maybe a few ml more, as some will be soaked up and retained by the coffee grounds).
For a single cup, we used to use one of those plastic cones, with a filter paper in it, which will balance on top of your cup or mug.