Start with a 1:16 ratio. That's one part coffee to sixteen parts water. For a single cup, that's about 30 grams of coffee to 480 grams of water. If you're using scoops, one scoop is roughly 10 grams, so three scoops for a standard mug.

This ratio is a starting point. Some folks prefer 1:14 for a bolder cup, others go 1:18 for something lighter. Play around and see what suits your taste. Write down what you used so you can replicate it or tweak it next time.