For there are different eigenstates of . There are two different eigenstates of for spin . We can have any combination of these states, implying possible product states like .
We will argue based on adding vectors... that there will be two total angular momentum states that can be made up from the 14 product states, , in this case and . Each of these has states, that is 6 and 8 states respectively. Since this gives us the right number of states.