Just jump in and DO IT!
This is the truth to the matter and no, it doesn't take "years" to develop. . . I can teach a person a bit more than the foundations of Muscle Reading in under an hour and having them do it. But there are a few "tricks" that you may want to use (one having been mentioned; insert MR stunts into your existing material as an experiment).
Introduce a Pendulum. . . it works on the very same principle and will allow you to gain confidence in working with it first, before moving to direct CMR.
GET THE BANACHEK BOOK & DVD! (Psychophysiological Thought Reading and Disc 3 of the PSI Series collection)
Aside from that Hanussen guide the Banachek material, especially the DVD, is the easiest to learn from and will help clarify things for you. If I remember right, Steve even offers suggestions about practice & development.
Practice with everyone you can, as often as you can. I used to have people simply hide things at random so I could track them down; today I find things they've "lost". . . but that's after nearly 40 years of practice.
There is a book from Hades Publishing on CONTACT MINDREADING by Shantz that you may want to invest in. He as well as certain of Bob Cassidy's published works, offers effects that you can do that look like true CMR which allows you to practice the technique while having a positive outcome. I don't like to encourage people to use the trickery cheats because they get lazy and rely on the trick vs. the real method. Effects that you can use however, would include Rick Maue's TERASABOS in that the CMR element will be your "out" should the psychology not work - you can verify if or not they have chosen the "correct" item.
CMR and Non-Contact MR are part of the ideomotor aspect of technique used in Mentalism and one of the primary skills every mentalist should master. . . you can (and many top pros do) present over 90% of your show using little other than this one skill set and do so in many different ways. Aside from the books & videos I've suggested here you may want to look into Jerome Finley's THOUGHT CHANNEL as well as Richard Webster's book
Dowsing for Beginners: How to Find Water, Wealth and Lost Objects . . . this is a non-magic book you can find at amazon.com for around $10.00 but it will give you another way of looking at this natural phenomena as well as a means of performance & practice.
Thought Channel is an intermediate level bit of business that deals more with Non-contact, but it will help you in discovering the physical nuances that you can use during a CMR routine that will help you know when you're on the right track. . . a series of natural "outs" so to speak. Besides that it's an awesome bit of empowerment that will allow you to out-do the typical magic buff when they are playing "sinner & saint" games with coins.
There is another treatise by Dale Heldibrandt but I can't remember the title. . . the technique can be found in other books, including Finley's CMR manual. The gist of the routine is that you and the participant hold hands palm to palm with your fingertips touching. You ask them to simply think of any finger and you can almost instantly name it. . . it is an excellent way of screening people and finding a good transmitter to work with in other experiments.
One last note. . . you want to pre-screen & qualify the person you work with in that you want a participant that gives off as strong a signal as possible. Oddly, some of the best senders I've worked with were self-described skeptics that hadn't a clue about how CMR worked. . . I usually made them believers as the result of the demo.
Keep your experiments simple at first. . . when you have articles on a table, separate them by several inches, narrowing the gap between items as you become more proficient. Understand that locating a hidden item is easier in most cases, than being able to I.D. a thought of card in a spread. Too, when you first start off locating items use something that's a bit larger than the proverbial hat pin such as a book or cell phone. . . the size will limit how well they can conceal the item as well as where they can place it. Also, restrict where they can put the item -- it must be readily accessible without the need to climb and of course, it can't be kept on the person sending you the signal.
One bit cheat I use when I locate objects in large areas is I have a committee hide the item and then, have at least 3 members of that group touching me. This works well when you've not been able to test out your transmitters in that you will always have one person in the trio that sends better than the other two. When doing this I have them placing hands on the back of my head (at the base) and on my shoulders, not the usual grip. . . I do change positions and dismiss participants when I know I'm getting closer to the hidden item but there are many nuances to learn to use here that we needn't get into.
While I'm not here as much as I used to be, feel free to ask away. This is something I've studied and worked with for decades in that I have family members that have done dowsing and pendulum readings for more than a few generations. . . it's a tradition with us.