Some good viusal aids and narrative that don't need youtube can be found here: http://www.wikihow.com/Roll-Your-%22R%22s

It is a challenging question from a distance, without feedback, and in written form. I love challenges. I found a good visual aid about 'r' sound, and this is the link: https://www.youtube.com/watch?v=4wEIsyqu_Jo It could set you back to the problem of watching a youtube clip, but this could be easier than the priginal problem. After you mastered the 'r' sound in one or more form, you may try to match an Italian speaker just using a spoken dictionary, or maybe trying to imitate the voice of a language partner. Spoken dictionary link: dictionarist.com Words I might suggest: Level 1: ridere,ridare,riuscire,ruotare,ricordare, Level 2: rastrello,trenta, trentatre. The 'tr' sound might be even more difficult. Try to repeat: al ritorno eravamo in tre sul treno.