Before brewing your coffee, it's important to consider your coffee to water ratio, also know as the brew ratio. The brew ratio is the amount of coffee used (by weight) brewed with how much water (by weight as well) to get your desired outcome. It's often represented in a format such as "1 to 15" or "1:15", where for every gram of coffee, 15 grams of water is used to brew. Naturally, the more water used, all things equal, the more diluted the final brew will be. It goes to say that a brew ratio is subjective; each coffee drinker will have their own preference in how strong (or less strong) they want their coffee. There is, however, guidelines that can be used as a suggestive recommendation. For pour over type coffee brewing, anywhere from 1 to 15 up 1 to 18 should satisfy most coffee drinkers' preferences. As a side note, it's worth mentioning that if you are adding a milk or a dairy alternative to your coffee after brewing that this would dilute the coffee taste and coffee to liquid weight ratio. The best way to dial in your coffee to water ratio is to first weigh out the desired amount of coffee on a scale to be used in brewing. To know the desired coffee amount, one must consider how much total water weight (+ coffee solids) is desired as the final outcome to drink. For me, I think between 200 to 250 grams of water weight is perfect for an individual serving. If I'm making coffee for more than myself, I'd take that into consideration and add between 200 to 250 grams of water weight per person. Once I've determined this number, I'd divide it by the brew ratio to get my desired coffee weight starting amount. As an example, 500 grams of water weight divided by a "1 to 17" brew ratio would give me around 30 grams of coffee to use (500 grams divided by 17 = 29.4 grams of coffee).
Now, I can take this 30 grams of coffee and put it in my brewing device. Next if doing a manual pour over, I'd tare my scale to zero and start pouring the 195 - 205 degree Fahrenheit water slowly over the coffee grounds. My target brew time is normally around 3-4 mins, and so somewhere between this range I'd like to be finished pouring the hot water over the coffee grounds so that when I've stopped pouring the total amount of water poured would measure around 500 grams on the scale. If your brew time is generally longer or shorter than this recommended time range then the coffee grind size probably needs some adjusting, which is a benefit of owning your own coffee grinder. Smaller of finer coffee particles are going to slow down the water pour over time, while larger or more granular coffee particles are going to decrease the pour over time. Generally, all things constant, too short of a brew time can lead to an under extracted coffee (which will taste overly sour) and too long of a brew time can lead to overextraction (which will taste overly bitter).
Thinking about and preparing your brew ratio is a good habit to develop in order to consistently make enjoyable coffee. Of course brew ratio and brew time is just one aspect of how your coffee will taste. What type of coffee you select, your brewing method, water quality, and grind quality/size/distribution will also have a large impact on coffee taste. Don't be afraid to experiment with your brewing. At the end of the day, guidelines are here to help guide, but it's really about how and what you enjoy drinking that matters most.
