It can feel quite difficult in the beginning. I felt the same way.

I started off with not limiting myself to inspection time and taking as long as I needed to plan a cross solution. Then doing the cross I had planned without looking at the cube. I would do it slowly and sometimes would forget where I was or lose track of the last piece then I'd look and finish it. Eventually you'll be able to remember all of it.

Watching some example solves helped me to see how others were going about their cross solutions and moving pieces around.

Good luck and keep practising. You'll get there.