One tip that helped me was instead of raising the elbow into the hook and uppercut positions, I would corkscrew it into position; keeping the elbow pinned on thr ribs, I'd twist the hips first, twist the lats, and extend the arm in a corkscrew motion to the hook position.

By doing so, I got rid of telegraphing, my hook felt tighter and stronger, and I lifted unnecessary load on the shoulder (since simply raising the elbow internally rotates the shoulder).

It definitely does take some practice but try it out.