Can someone help me out on the dream walk process?

I've been practicing entering other people's dreams for a while now but i can't seem to get into there dreams. I've already mastered lucid dreaming and i contacted my friend so that we could try to enter REM at the same time. Also if there is someone out there who has mastered dream walking please send me an email after you've answered the question. In advance i'd like to say thank you. Happy dreaming :)