A good drying room will need to be dark with temperatures between 60-70°F and humidity between 55-65%. A cheap hygrometer will help you monitor these numbers.
Depending on your house or property, you may be limited in what you can use for a drying room. Know that it can be hard to control temperature and humidity in big rooms. Also, know that the room will smell like weed. Be sure the space you choose doesn’t have huge fluctuations in temperature and humidity.
Add a small fan to circulate air, and you may need to add a dehumidifier or AC as well. If it’s taking too long to dry buds in your space, you may need to adjust the temperature or humidity to help the drying process.