Advice on writing strong character descriptions?

 Like the rest of screenwriting it's about making the reader feel how you want them to feel about a character. In Knives Out, Rian Johnson's script describes a character (played by Don Johnson)as  "He would put his feet up anywhere" and it really gives you an idea of how you see them. In The Menu, you get very little out of Margot and Tyler when they're first introduced, just that they're a young, elegantly dressed couple, because that's part of the mystery. 

 I think just reading more screenplays can help give more ideas of what that looks like.