"Is this the right bend?" is one of the most common question I get asked during clinics.
When riders ask this, they are looking for a shape to put their horse in. They want to know how much the neck should be positioned to the right or left, and what shape the horse should have through his body.
My answer usually steers them away from thinking of the shape of the bend, and towards the function of it.
The best way to start practicing bending is when you are on a bending line. In that situation, the purpose of the bend is to be aligned with that bending line of travel. When you align your horse on that line you will have arrived at the 'correct' bend.
There will be evidence. Your horse will tell you because he will feel different than when he is in any of the 'not aligned' or crooked places! Sometimes it is easiest to understand this by imagining if you were really crooked to the line of travel, (see the figure above from the Dressage Naturally book). If you were crooked, then most likely one side of the horse would be tighter feeling, or the rhythm would not be as clear, or there would be a tendency to drift (or lean, or pull, or pop-out) off the line of travel.
It makes sense that when you are aligned, the horse will feel more rhythmic and focused, like his body and mind are carving the circle. You will need fewer adjustments or aids to sustain this alignment when the horse 'hooks on' to the line of travel. The horse will feel the ease, too!
Get more crooked, then go back to neutral. Ask the haunches a little too far right, then neutral, then a little too far left, then go to neutral... Do the same with the shoulders, neck, and head. This exercise is what I call The Basic Alignment Exercise. You can find videos teaching you about it in my book/DVD and Video Classroom.
I promise if you play with this, you will start to feel the difference AND will instinctually start to prefer the place of alignment. This place of alignment will feel easier to your horse too. He will actually start to seek it! This is simply the fastest way to find 'correct bend' (which is secret code for 'alignment on the circle').
Gently experiment with great feeling Listen to your horse. Be prepared - what your horse says he needs in order to feel aligned may be quite different than what you thought you would need to do to find 'correct bend'. Go with it anyway! As he spends more time in that functionally aligned place, you will start noticing it looks more and more like what the textbooks say.
Watch videos of Karen discussing and coaching students through this concept in The Video Classroom. Login and navigate to January 2013 Videos (or search for Bend)
After you have a sense of what that bended alignment feels like, you will then be able to recreate it in other moments (such as for counter bend or in lateral work)
Doing it this way focuses on the FUNCTION of the bend, instead of just trying to create an arbitrary shape. This makes it easier to find without mirrors or an instructor. Best of all, it allows your horse to participate in the process.