How do you apply the Jack Dempsey drop/trigger step to the right cross/left hook?

[OMGWTF]

Grey im finding it hard to find the sweet spot of when to twist my foot/hips after ive stepped in, I found it hard to learn how to spin my hips when stationary now when im moving in then throwing the cross I find theres less weight on my back foot as I bring that rear foot up and for me when theres less weight on that rear foot I find it hard to rotate my hips with any power. Is it just a case of more practice or am I missing something still?

Ive noticed like you said the moment my front leg plants it becomes the pivot point for the foward momentum, and turns that foward momentum into a rotation.

Edit: scrap that Grey I was doing another old habit of twisting from the waist instead of from the foot/hips as I stepped in, so now I twist the rear foot the moment I bring it up and it twists my hips as normal.

Thanks again mate!!!!!!!!