I have recently switched from a traditional putter to a belly putter?

Using a mid-length putter is not much different from a standard-length model. Take your normal putting stance and grip, but anchor the shaft in your midsection. Your height and body shape will dictate what length putter you should use.
The Stroke
The anchored shaft does one critical thing for your stroke -- it acts as a stable hinge point. Your options for powering the stroke are the same as with the long putter. You can put the putter in motion by using the right arm or by moving the shoulders and upper torso.

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