The fifth and final step of the slice backhand is the follow through. From your contact point, extend out in the direction you are hitting, and let your arm naturally rise to decelerate the tennis racket. This may seem unnatural at first to follow through in an upward direction because you were swinging down on the ball initially to create backspin, but because of the way your arm is built it will naturally rise after contact and the racket will slow down.
From the side view at 0:30 in the video above, after contact my arm extends out and begins to rise naturally. Also notice that the relationship between my hitting arm and the tennis racket doesn’t really change much after contact. At the end of my follow through, the racket’s strings will end up facing the sky.
The other critical part of the follow through is that your body needs to stay sideways as you follow through. To make sure that you stay sideways on the follow through, leave your non-hitting hand back behind your body. Finally, notice that as I make contact I am looking at my contact point, and during the follow through I continue looking at my contact point.
Let’s now take a look at Oliver following through on the slice backhand at 1:08 in the video above. He extends out after contact, and the tennis racket continues moving downward (from his forward swing) for a split second after contact until it naturally begins to rise again. At contact, his strings are facing the net, but by the end of his follow through the strings are pointed up at the sky.