Probably the biggest advice given to other artists is study the art form you want to replicate. Want to write books? Then read. Want to make movies? Watch movies. Simple, well sorta. Watching, reading, going to galleries on its own isn’t really enough. You’ve got to have your brain engaged to figure out why the movie, book, painting is awesome.
Even as a book writer I like studying movies and tv shows. A friend of mine recently said that he’d love it if tv script writers wrote books because they’re great at characters and their dialogue, something generally lacking in the book world, so a favourite past time of mine is a character study. I sit down with a book or tv series and I focus on one character and their dialogue. If it’s film I also focus on their body language, eye contact and all sorts of things like that and if book I focus on the repeated expressions, what makes them angry.
I talk to other friends too about why they might like or dislike a character and then I often try to write some fan fiction, where I take everything I’ve learnt about that character and they way they talk and try to apply it. While this can sometimes result in work I can’t sell it can also result in some amazing pieces where I learn what sorts of things makes a character a character.
On top of that I find reading description heavy authors like George R. R. Martin great for my own descriptions. It helps me figure out what sort of details should be woven in amongst the rest. Some people like getting lots of description and place setting, but the true greats describe everything without you feeling bogged down in paragraphs of boring information. Studying their tricks and the way the build their scenes can be a great help.
Finally every writer, actor, and director has their own style and while this shouldn’t be copied out right as it’s way better to develop your own style it can be a great way to learn what sorts of things people like. You’d also be surprised what people do and get away with and what rules are deliberately broken and when. Sometimes a style can be particularly known for breaking a rule, like Stephen King tends to have long sentences and many authors will play around with the exact useage of commas and occasionally words. If there’s a good enough reason for something there really are no rules.