I find that my shooting is very inconsistent. I suspect that the source of my problem is that, despite stalking the ball, I end up with my shoulders not at right angles to the target ball. To compensate for this, my mallet comes through at an angle. I should point out that all of this is subconscious and entirely unintentional. I suppose it is also possible that I subconsiously aim to one side of the target ball to compensate for the fact that I don't swing straight.

The more I practice, the more I seem to reinforce these bad habits.

Can anyone suggest some practice routines to help eliminate these problems and improve my shooting consistency?

First find out if your suspicions are correct or not. Find a coach or observer, or perhaps videotape yourself shooting. Bad shots can come from poor aim, poor swing, or both.

I think of the goal of stalking as getting your feet into the right positions. One common problem is ending the stalk by planting the first foot too close to the intended line of aim, then placing the other foot based on the positions of the first foot and the striker's ball. If you plant the right foot first, this results in aiming to miss to the right. I think this is often a dominant eye issue: if you rely on one eye while stalking you are likely center not your body but your dominant eye on the line of aim.

Timing and tension are also common causes of poor shots.

Two things I did to improve my swing.

Inspired by Reg's swing trainer I used the poor mans version of bisque sticks. Create 2 parallel lines of approximately 8 bisques [See similar bisque sticks in Bath Croquet Club.] each a little wider apart than your mallet and practice shooting. It doesn't test your swing at the top but certainly does at the important point of impact.

I practice hitting a plastic golf practice ball on the end of elastic as opposed to a spiked croquet ball. Keeps your focus very narrow and then when playing a game the croquet ball looks like a beach ball in comparison.

When initially developing my swing and whenever I feel I need remedial work I follow this routine.

Day 1: 16 roquets onto golf ball from 2 yards. If hit all 16 move back one yard. Hit 16 more, if all hit then back one yard otherwise 16 more attempts. Total 48 roquets.

Days 2 to 30: Start at distance where 16 were hit the day before. Repeat as in day one.

A few suggestions.

1. Video yourself — if you can't do this watch yourself in front of a mirror. The most important part of doing this will be to see where you are striking the strikers ball. It is amazing how many people don't hit this in the middle.
2. Try to visualise your swing. Then work on two aspects. The first 6 inches of the backswing and the last 6 inches before contact. If you can reinforce what it feels like to get these areas right, your shooting should become more consistent.
3. If you don't play with your hands together, start working towards it. The swing should come from the long levers (shoulders) not the wrists.
4. Try thinking about hitting the strikers ball on the far edge. i.e if you normally hit it at 9 o'clock, imagine hitting it at 3 o'clock. This should help you to generate a good follow through rather than stabbing at the ball.
5. Practice routines.
   Place two balls on the boundary line and another two 4 yards away. Take both shots, making sure to take plenty of time between strokes and to stalk properly. If you hit both, move back 2 yards, if you miss both move forward two yards if you hit 1, stay where you are. Repeat 11 times so you have taken 24 shots. Do not do more than this at one session since you may start practising tired which is of no benefit at croquet.

Hope that's of some help.

As well as the many suggestions, I'd suggest looking at why the mallet isn't following through straight (this is if I've understood your comment "my mallet comes through at an angle"). I used to have a problem with this, which I eventually put down to two things.

1. Grip. With my old grip, the mallet head used to twist by about 5-10 degrees if I tighted the grip. In effect, this meant that for presure shots (or after having missed the previous few), the mallet inevitably wasn't pointing forwards when it struck the ball. For reasons I don't quite understand, the error in direction was much less than the angle of the mallet, but it clearly didn't help!
2. Hitting the centre of the ball at your feet. It's very difficult to tell this yourself until you get a good idea of what the strike should feel like. I suggest you need a coach/friend to look (probably from behind) as you strike a series of balls to tell you if you're hitting centrally. If you can't hit the centre of a ball that's at your feet, your chances of hitting a ball thats 10+ yards away are very slim! Once you know whether it's your swing or your aim, you'll be able to concentrate on the cause of the problem.

As for a practice routine, there have been at least two suggestions along the lines I'd suggest (hit N shots at a given distance. If they all hit, then increase the distance. If some miss, then decrease the distance.) When I do get time to practice (which rather oddly was not often enough last year), I usually use some time doing this. If there is enough time during a warm up at the start of a days play, I sometimes use the same routine with N=1 as a easy way to get the basic swing warned up.

I, right-handed playing with a standard Solomon grip therefore with my left hand on top, also had the same problem.  I have (more or less!) dealt to it with the following changes to my grip which have helped to steady up my hitting after tending to go to the left of the target ball:

1. First change was to ensure that the knuckles in the middle of my fingers were in line down the front of the mallet - which had the effect of bringing my elbows into my sides ands hence a straighter swing.  (I know Paul Skinley doesn't play that way, but it works for me.)
2. Depowering my right [lower] hand so the it didn't "grip" the mallet — as Samir explains — as I swung through the vertical, by locking the index finger of my right hand over the little finger of my top hand and placing the fourth and fifth fingers of my bottom hand behind rather than in front of the mallet, thus leaving only my middle finger on the front of the mallet where it acts as more a steadying influence than anything else.
3. Having a longer-headed mallet!  I had a 10-inch long peripherally weighted Puckett head, but Ray persuaded me to try an 11-inch one, and — mirabile dictu! — the change in the percentage of successful roquets (I daren't say from what to what!) has been very noticeable.  Thank you very much Ray.
4. Also, of course, endeavouring with a little more success than in the first ten years of my playing to keep my eyes on that specific bit of grass just behind the ball right through the swing.

I should also add that I have had much more success with my roqueting since I took up golf croquet some three or four years ago.  Perhaps because so much more of Golf Croquet is shooting at another ball than in association croquet I have become much more relaxed about these sorts of shots.