Do's
Be nice to everyone, remember they are people, just like you. Just because you're shifting their doesn't mean they cant feel feelings.
Script that nobody you love can die.
Script that you don't feel pain (or not as intensely).
Script you don't have a period (this is just a blessing, one of my favorite things about shifting for sure).
Script you cant die (if you do die you just come back to your CR).
Don'ts's
Don't script that your the most powerful, its not fun, its actually pretty dangerous. (unless you script Voldey out but I still don't really recommend).
Don't force yourself on someone, remember they are just as human as you!
Don't cause mass genocide.
Don't tell people you shift, it gets really awkward.