Welcome to the forum!
I want to start lunging my two shetlands that are 3 and 4 years old. I have got a lunge line whip and caversson. I had a go but they only walk if someone is on the other end leading them otherwise the just walk towards you. So what am I doing wrong?
All help will be much appreciated
Before introducing lunging proper, make sure that your ponies understand how to yield to pressure: if they know to move their shoulders and haunches away from light pressure, and how to back up, you've got a bit more of a foundation to build lunging on.
Body language is extremely important in lunging; if you are ineffective in your position, or the horse does not understand your properly executed signals, you're going to run into problems. Don't worry about making the circle very big at all to begin with, and start at the walk. Going on a clockwise circle your line should be in your right hand, your whip in your left, forming a triangle with you at the apex and your pony at the base. The trick is to increase your energy in such a way as to drive the pony out and forward; "glare" at the pony's hip, and if you need more forward, use your whip to "get" the spot on the ground
where his hind feet are -- getting the ground encourages the pony to vacate the space without feeling as "chased" or stressed. Also, be sure to raise your line hand high and point the direction you want him to go; open the door, and make it very clear where the opening is.
Start small - even if you're walking a huge circle with your ponies on a short line. Get the basic idea where you are close enough to decisively correct mistakes, and feed the line out as you go. Again, think carefully about your body language and positioning. If you put pressure ahead of the driveline (the girth is a good reference point if you're unfamiliar with this idea), the horse will slow down, stop, or turn away from you. Pressure can be as slight as you standing ahead of the driveline. Pressure behind the driveline will cause the horse to move forward or speed up. Proper positioning will ensure that you aren't telling the horse something you don't want to say, and clarify what you do want to say.
I hope that is helpful to you... sometimes these positioning things are difficult to explain through text. If you're a more visual learner, look up some youtube videos to get some illustration in action. Clinton Anderson is great for the respect and control aspect of it, as well as the concept of the "drive line," even if you don't go for his exercise per se. I love Dennis Reis' discussions of body language and intentions, and how to really know what you are telling the horse. The idea of "getting the ground" with the whip I borrowed from Pat Parelli. I personally take a NH approach to groundwork and lunging, but the above advice is still quite applicable to the first baby steps of classical/formal lunging, if that's your ultimate goal. As always, it's best if you can get someone experienced with lunging and teaching youngsters to lunge properly and safely to help you in-person to get you all started on the right foot. One final thing to keep in mind is the age of your ponies; at 3 and 4, they are still youngsters. I'm not an authority on Shetlands, but a 3/4 year old QH, TB, Morgan, etc., would still very much be developing bone structure at that age. Take care not to overwork or stress young legs with long sessions or overtight circles, and look into protective boots or correctly applied wraps to support their legs if necessary.
Sorry for the small novel....