There is no doubt that overarm bowling is the most difficult cricket skill to master
However, like all the other skills, improvement comes with practise. The two most important aspects are that the bowling arm should be almost straight at the elbow (the rule says that it can have up to 15 degrees of bend but no more) and that that the shoulders and hips are in line at the point of delivery.
The Mixed Action
One thing that junior players regularly do is to mix their action. There are two variants of the basic bowling action:
A side on bowler will plant his back foot down sidewards with hips and shoulders in line pointing roughly towards the batsman.
A front on bowler will point his back foot forwards towards the batsman with an open chested delivery action and his hips and shoulders roughly at right angles to the pitch..
A mixed action combines elements of front and side on actions resulting in undue stress on the spine. This is the reason behind the ECB's restrictions on the number of overs that under 19s are allowed to bowl.
If a coach tells you that you are 'mixing your action' then it is nothing to get too worried about, but you need to listen carefully to your coaches who will help you correct it over time and ensure that you don't get injured.
As a general rule it is much harder to change the way a bowler plants his feet than it is to turn his shoulders. For this reason your coaches won't change your feet position but they will work with you to get your hips and shoulders in line by changing your upper body position as you bowl.
Imagine two lines, one running through your hips and one running through your shoulders. When you bowl these two lines should be almost parallel - like this:
This is an example of a side on action.
This is an example of a front on action.
This is an example of a mixed action where the hips and shoulders are not in line with each other.
To understand how a mixed action can damage your back, stand sideways on and completely still. Now slowly rotate your hips and shoulders until your head is facing forwards at around 90 degrees to your upper body.
Can you feel the tension and twist in your spine?
Does it feel comfortable?
A mixed action creates that tension and discomfort every single time you bowl so remember the saying:
"Keep the hips and shoulders in line and you'll be fine - twist the back and it will crack!"
What Type of Bowler Are You?
We all have our bowling heroes - who are yours? Does it make you want to bowl like they do?
When you start to bowl you may try seam, pace and spin bowling before you find your preferred style. Some bowling actions are particularly suited to spin and your coaches will work with you to find what suits you best.
Once you decide on a style, it's important to practise it and not keep adding in 'a couple of spinners' if you are a seamer or some 'quicker deliveries off a long run' if you usually bowl off spin. This just doesn't work and we see juniors doing this all the time and getting hammered all round the field by batsmen who frankly can't believe their luck when a quickie suddenly bowls them a gentle full toss!
So stick with what you know and work hard to get better at doing it!
Are You Over or Around The Wicket
Bowling over the wicket simply means that your delivery arm is closest to the stumps - bowling wicket to wicket. This will generally improve your accuracy when you are first learning to bowl. Most right handed bowlers bowling to right handed batsmen will bowl over the wicket. Left handed bowlers bowl over the wicket from the other side of the stumps and will also usually bowl over the wicket at right handers as they naturally angle the ball across the batsmen which makes it more difficult for them to judge the shot. If you happen to be a left handed bowler - make good use of it as it's a very valuable gift!
Bowling around the wicket means your delivery arm is furthest away from the stumps and it enables you to angle the ball in to a batsman. Right handed bowlers sometimes like bowl around the wicket to left handed batsmen. You can vary the side you bowl from during an over but you must inform the umpire of any change so that he can notify the batsman. A no ball can be called if you bowl from a different side without telling the umnpire first.
Note that left-handed batsmen are used to the ball being angled into them from a right-handed bowler coming around the wicket. You may be more likely to unsettle a left-hander by bowling over the wicket - particularly if you can swing the ball away from the left hander or bowl a leg-cutter (as a right hander bowler this would be your normal inswinger or off-cutter but for left-handed batsmen the impact of these deliveries is reversed).
The ABCD of Bowling
A is for AGILITY As you run in to bowl make sure you are not running in flat or heavily, you need to be loose and relaxed to bowl well, not tense or stiff in your action. Try to make you bowling action smooth and flowing.
B is for BALANCE You cannot bowl well if your weight is on the wrong foot or your run up is not balanced. Keep your weight even as you run in and lean back slightly as you bound off your back foot before delivering the ball.
C is for CORRIDOR Keep your run up straight - imagine a narrow walled corridor that starts at the top of your run up and continues all the way down the pitch to the stumps at the other end - your job is not to hit the walls.
D is for DIRECTION The place to aim the ball is between the line of the stumps and the area just outside (on the opposite side to the batsman's legs). We call this the off side (nothing to do with offside in football). Where the batsman stands is called the leg side (for hopefully obvious reasons) and bowling on the legside is likely to result in heavy scoring by the batsman and very few wickets for the bowler.