Are you giving the coaching or just participating? If it's the former then you could look for inspiration on youtube, if it's the latter then perhaps keep an open mind and see what the coach has in store for you.
I am not a coach either but a few things I remember from when our coach addressed this about 6 months ago:-
- reading line is easier than length
- reading length is easier than reading both at the same time to a good spinner who puts top/ overspin on the ball and can get dip...
- so you need to learn it in steps e.g. exercises focusing just on merely getting to the length before focusing on actually playing into the gap
- one of the many problems of just charging is losing shape/ squaring up, head falling over, eyes coming off the horizontal, you may pick the wrong ball, you may become predictable, you may miss the ball!
- breaking it down might mean doing exercises just making sure you move side on - NB some people will shuffle, some will prefer to cross one leg behind the other
- I think our coach had us trying to catch balls after one bounce at ankle to mid calf height on its way up whilst advancing sideways down the wicket from the batting crease;
- need to keep head still and on a level whilst moving forward
- following the ball from the hand with maximum focus throughout the flight
- cues may be taken before the release, e.g. do they wind up (will be flatter and faster), is the run up or release different, is the angle of release different? This kind of focus I think really takes practice!
- the one thing he really impressed on us was picking the length was most important, and he was quite averse to premeditated coming down the wicket, but if you can't pick it and you're going to go, then you better get something on it or might as well keep walking all the way back to the hutch!
- the session also included back foot drives I suppose to balance things up.
Hope this is of some use. It has reminded me I should go work on it again!