Add an appropriate amount of kava powder and water to a bowl and mix. The amount of water you will have to use depends on how much kava you are preparing. Just be sure to use enough water to turn the powder into a liquid. It is easier to use kava powder in liquid form as compared to a paste.
Cover another bowl with cheesecloth and pour the kava powder liquid through the cheesecloth. This will strain solid kava powder particles from the liquid so that they do not get into your drink. Consider straining the kava powder twice or even thrice just to be on the safe side. Once properly strained, the kava powder will be ready for you to use.
Tradition dictates that kava powder drinks are meant to be consumed from coconut shells. Obviously that is a little hard to manage; in order to try and comply with tradition, however, consider drinking the kava from a bowl instead of a glass. Simply pour the liquid into a bowl, and drink it.
Kava powder can make you fall asleep rather quickly, depending on the amount of powder you used and the concentration of the drink. If you do not fall asleep, you will feel dazed or sleepy for a while. For this reason, it is best to either have it before bed, or when you are not required to perform tasks that need concentration, like driving.