The amount of coffee grounds you need per cup depends on a few factors, including the type of coffee maker you're using and your personal preferences. For instance, if you're using a drip coffee maker, you'll need about 2 tablespoons of coffee grounds for every 6 ounces of water. If you're using a French press, on the other hand, you'll need about 1/4 cup of coffee grounds for every 4 cups of water. And if you like your coffee on the weaker side, you might want to use less than the suggested amount of coffee grounds.
Keep in mind that these are just general guidelines - ultimately, it's up to you to experiment and find the perfect ratio of coffee grounds to water for your taste.