Ave Rebel et al,
The application of renwax is Your Friend when it comes to bringing out details on worn coins/artifacts, especially those with green patina. The wax not only protects your objects from the atmosphere, but also helps darken the patina to an eye-pleasing color.
I apply the wax with my thumb and fore-finger, just to fully work the wax into all the surfaces. This ain't rocket science, no Q-tips, please. Just like waxing a car, the more coats the better. The trick, as mentioned above is to let each thin coat of wax to fully dry, then buff. I use a special Dremel buffing tool. You can simply place your coin onto a soft cotton towel, gently press down and buff it about in a swirling manner. The more coats the more you'll begin to see the 3D effect of the multiple coats.
Hope this helps,
Kevin