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

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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