How can we build the spin 2 graviton representation of little group O(9) in QFT?

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The spin 2 graviton representation of the little group O(9) in Quantum Field Theory (QFT) is defined as a symmetric traceless tensor with 44 independent components, as detailed in Weinberg's QFT Volume 3. The components include one with J23=±2, seven with J23=±1, and twenty-eight with J23=0. The tensor's rank is 10, not 4, due to the specific representation of the little group, which dictates the number of independent components. The traceless condition arises from the physical requirement that the graviton must be massless.

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fxdung
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In QFT vol 3 of Weinberg write:''For d=11 the spin 2 graviton representation of little group O(9) is a symmetric traceless tensor with 9x10/2-1=44 independent components:there is one
2+(-)i3,2+(-)i3 component with J23=+(-)2, seven2+(-)i3,k components with J23=+(-)1; and twenty eight k,l components with J23=0(here k,l run over the seven values 4,5,6,7,8,9,10)''
I tryed but fail to build the tensor.How can we build the tensor?I do not know why there are the senven and twenty eight components of J23=1or-1 and J23=0?Why does the tensor has rank 10 but not rank 4 because j=2=4x1/2?Why is tensor traceless?
 
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PS:QFT of Weinberg Vol 3 page 395
 

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