Using the proper technique is probably the most important thing to learn if you are an archery beginner. Good posture and good balance are important as you stand and draw. Your feet should be comfortably apart for balance. Your bow arm should be kept straight as you draw and the draw (string) hand should be brought back to touch your face, you take aim and release the string to propel the arrow, hopefully toward the target. This a very simple description but once the basic motion is well developed it can be perfected and then repeated for each shot.
A common mistake made by archery beginners is to gripe the bow too tightly. It should be held it a loose and relaxed grip. Holding the bow too tightly can lead to twisting and turning of the bow and thus throwing the shot off. As for the grip on the string the traditional three finger grip generally will work fine. This requires the index finger to be above the nock and then the ring and middle fingers below the nock. Keep enough space between the index and middle finger so you do not pinch the nock. Apply equal pressure to the string with each of the fingers.
As you draw the string back to shoot you want to pause and aim when you reach a certain point, known as your anchor point. Developing your anchor point is a key to developing accurate shots. The anchor point is the exact location of where your draw hand is brought back to touch your face. An example would be to have your index finger touch a certain location on the side of your chin and the bow string to be just in front of the tip of your nose. Assuming this allows for good aim you should use this a reference point so you can duplicate each shot. Consistency is what you are striving for. Remember to allow for good follow through on each shot as well. Do not make the mistake of moving the bow arm at any point as this can easily mess up the shot completely. Keep you arm, legs and head stable. A good rule is to stay still until your arrow has hit the target.
Another important point to keep in mind is to stay relaxed and do not tense up as you are shooting the arrow. Relax, stay focused and have fun. Being nervous or too tense will make it difficult to make accurate shots. This is true in many sports application, weather it is hitting a baseball, shooting a basketball or casting a fly rod.