Increasing your knowledge of basic fundamentals will build your level of consistency
Grip, Aim, Stance, Posture
The way the fingers are placed on the golf club will have a direct relationship to the flight of the ball. If you do not grip the club correctly, you won't to hit the ball straight.
The 10 Finger Grip is used primarily by junior golfers up to the age of 11, due to their lack of strength. It is difficult to control the weight of the club.
The Interlock Grip is used primarily by golfers with smaller or weaker hands.
The Overlap Grip is used primarily by golfers with larger or stronger hands.
The "v" between the thumb and forefinger of each hand should point between the right ear and the shoulder (for a right-handed golfer). Moving the left and right hands further to the right is considered a strong grip, while moving the left and right hands further to the left would be considered a weak grip.
Having correct aim and alignment will help you identify swing flaws much easier.
An intermediate golfer rarely checks their alignment, yet advanced golfers check their alignment at every practice session. This fundamental is simply just overlooked. Most swing path problems occur because the golfer simply aims poorly and has to adjust for poor aim by swinging an outside-in swing path.
The golf ball is your target and the pin is your final destination. Drawing an imaginary line between the two will establish your aim line. Pick a spot about 3 feet in front of your ball on your aim line and use this spot as a reference for addressing the ball and aiming your club face.
When addressing the ball, keep your body square to the target line and position your feet and the ball appropriately for the club you are going to use. The line of the tips of your toes, knees, hips, and shoulders should be parallel to your target line. Position the club behind the golf ball with the clubface pointed squarely towards the spot in front of the golf ball. With strong swing fundamentals and proper alignment, the flight of the golf ball should be straight towards your final destination.
Aim and Alignment
In order to build a solid game you must build a solid foundation.
Your stance should be athletic and create a foundation for your swing and stability for your body to maintain proper swing mechanics and transfer power to the ball. To maintain an athletic stance and solid foundation you need correct weight distribution. At address, your weight should be in the center of your feet between the ball of your foot and your heel. If your weight is on your heels, this will cause you to lift up during your backswing, top your shot and lose your balance. If your weight is on your toes, this will cause you to fall forward, hit behind the ball and lose your balance during your swing.
Stance width is also critical to the foundation, balance, weight shift and swing mechanics. The width of the stance is determined by the club length - the longer the club, the wider the stance. The stance should be shoulder width apart to the outside of the feet beginning with the wedges through the 5 iron. From the 4 iron through the driver, the stance needs to be wider and thus, shoulder width apart to the inside of the feet.
A great way to check your stance width is to place the head of an iron under your arm and let the shaft hang straight down along your side. If your feet are shoulder width apart to the outside, the grip will be over the outer part of your foot. Similarly, when your feet are shoulder width apart to the inside, the grip will point to the inside of the foot.
Ball position is also determined by club length. To ensure that you are standing at the correct distance away from the ball at address position, you should set your feet such that your chin is over the front of your right hand when using a shorter club (8 irons through wedges). As club length increases, so should your distance away from the ball. For mid-irons (5,6,7), the chin should be positioned over the front of the left hand, and finally, for the longer clubs (4 iron through woods), the chin should be at the butt end of the club. Standing too close to the ball with a longer club will cause you to hit behind the ball resulting in fat shots because there is simply not enough room to freely swing the club. Conversely, standing too far away with a shorter club will result in topping the shot since the club is not long enough to hit down into the shot. Ball position is crucial to impact.
Ball position within the stance is also determined by club length. The ball position for the wedges, 9 iron, and 8 iron are in the center, while longer clubs begin to move forward in half inch increments until you reach your driver which is played off your left heel.
Stance and Ball Position
Developing a proper swing can only be done if the body posture is correct. The proper posture will help you get into a position to where your body can move freely. The correct posture will set your body in a good balanced position that will allow for balance in the golf swing. Posture is the base around which the club is swinging. It is the framework of the swing and crucial that a good balanced posture be implemented into your pre-shot routine.
To achieve perfect posture, stand straight up, hold your elbows into your sides with your forearms positioned parallel to the groundm and hold the club at a 45% angle.
Bend over at the waist (sticking your hip pockets out) without physically moving the arms or the club, but allowing them to move as a result of bending, until the club is parallel to the ground.
Once the club is parallel to the ground, drop the arms and the club from this position and let the club head come to rest on the ground. At this point, the arms should be hanging straight down from the shoulders and the bottom hand on the club should be at the end of the toes.
Bend the knees slightly or softly so they stop when your knee caps (if you were to draw a vertical line) are in line with the balls of your feet and your shoulders. Adjust your feet closer or father away from the ball until your body weight is centered on your feet and underneath you.