As an SLP, I have learned a few things are true when it comes to the R sound...
1. It is one of the most commonly mis-articulated English phonemes
2. It is one of the trickiest phonemes to teach in speech therapy
So, I have recently turned my speech therapy room into a "Speech Gym" for many of my students working on tricky sounds like R. Just recently, I was in a group with two students who want to quickly "fix" their R. After hearing them continue to misarticulate their attempts (despite my cues to slow the process), I talked to them about training for the "R Marathon". So, I'm not afraid to admit, I am NO runner. . .so, this was my analogy. I told them that if I started trying to run tomorrow without any training for it, I would keel over within the first 10 minutes! So, this is where training and exercise come in, and now we are training for the R Marathon. For my students who have minimal stimulability for this sound, I ALWAYS start with oral exercises to build stability of the jaw and mobility of the tongue. I have a few books from Pamela Marshalla that have guided me on this quest, and I would HIGHLY recommend them. I recently got her book "Successful R Therapy". Check it out here:
From this book, I found a new exercise that I started using with a few students and I am already seeing some success! The rule is Do Not Make A Sound, Try Not to Say the R sound. This is recommended by Marshalla in order to keep them from reverting to their old habits. So, if you are like me and always looking for new ways to make treating R a little easier, try this on for size! Here is the visual I created to send with my students so they can practice this exercise in therapy and at home.