Unfortunately, you don't. The D3000 does not have an autofocus motor; it relies on the the lens having one. This particular Sigma lens, unlike its Nikon equivalent, does not have a motor.
Nikon calls their lenses with an autofocus motor AF-S. Sigma calls theirs HSM.
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Unfortunately, you don't. The D3000 does not have an autofocus motor; it relies on the the lens having one. This particular Sigma lens, unlike its Nikon equivalent, does not have a motor.
Nikon calls their lenses with an autofocus motor AF-S. Sigma calls theirs HSM.