Shooting a bow and arrow accurately and consistently takes practice, albeit gaining the ability to group arrows in tight groups takes more than just practice it takes proper practice. You can't just shoot arrow after arrow and become consistently accurate without implementing the proper techniques, form, and practice habits.
Concentrate on a tiny spot on the target. The smaller the better! This helps because it requires you to concentrate more than if you were shooting at a larger spot on the target. When shooting it is key to concentrate on the spot that you are wanting to hit. Nothing else should be on your mind. Keep your eyes on the spot while you draw, anchor, aim, release, and finally watch your arrow hit the target.
Shoot with both of your eyes open. Shooting with both eyes open helps in low light conditions. It also helps watch the arrow as it finds or misses it's mark. While shooting with both eyes open, your eyes may battle for dominance while you begin to aim. If this happens, close your non-dominant eye for a second regroup and open it again.
Relax your fingers while holding your bow. You do not want to have pressure on the grip of the bow from your palm. But, instead you want to allow the bow to be held in place by the v between your thumb and index finger. This will help to prevent your from torquing your bow during the shot. Which is a common cause of inconsistency.
While aiming at the target, and ensuring that your pin is in the small tiny spot on the target, start squeezing your trigger on your archery release, but all the time concentrating on the tiny spot on the target. Keep squeezing slowly and concentrating. You do not want to know the exact time the bow is going to be released. Keep your bow in the same position while you watch your arrow find it's mark.
Shoot bright color vanes. My favorite color vanes is white. I prefer white because it really stands out against a dark target. They also make it easy to locate your arrow if you miss or shoot through the target. The only concern with white vanes is while hunting, especially during gun season. For safety, it is recommended to cover the white vanes with hunter's orange when walking through the woods.
Practice shooting your bow at long distances. Shoot at 45 yards or more! This will magnify any imperfections in your shooting form because the farther you shoot the more your imperfections will impact your arrow flight. Practicing at long distances will also make it seem simple to shoot the 20 to 30 yard shots!
Shooting a lighted arrow nock, such as a Lumenok is a great method at long distances to see imperfections in your form. With a lumenok attached to your arrow shoot your bow 45 plus yards and watch the arrow as it flys to the target. The lumenok will help you to see imperfections in your arrow flight. It will also make it easy to see where you hit the target and to recover your arrow in low light conditions.
The next time you decide to shoot your bow, be sure to consciously aim at a tiny spot on the target, clear your mind of everything but the tiny spot on the target, shoot with both eyes open, relax your fingers on the bow, squeeze the trigger on the release, keep your bow in the same position after the shot while watching your arrow hit the target, shoot bright colored vanes, practice at long distances, and shoot lighted arrow nocks to discover imperfections in your form. I am confident that implementing these techniques will improve your archery shooting.