Spinor bundle

For the moment, what I have is this:
Given the smooth oriented Lorentzian manifold (M,g), we have the tangent bundle TMM.
We also have the SO(n,1)-orthonormal frame bundle, PM. Now, as we know, TM is the bundle associated to P via

TM=P×SO(n,1)Rn+1

(see associated bundle).
Since SO(n,1) has the double cover Spin(n,1), we suppose the existence of a "kind of double cover bundle" of P, i.e., another principal bundle Spin(n,1)QM, with a double cover map ϕ:QP (with some additional requirements. I think this is what is called spin structure (see also spin structure in Wikipedia). We then take a vector space Δ over which there is a representation of Spin(n,1), this is where the Clifford algebra comes in. The spinor bundle is finally S=Q×Spin(n,1)Δ. So the spinor bundle is a vector bundle associated to the double cover of the orthonormal frame bundle.