I don't like to post much about writing how-to's. Largely, the reason why is because writing is a creative endeavor, and creativity is a personal thing. What works for one person, doesn't for another. This is the most confusing and mysterious thing about working as a creative: the journey to being productive is a self-discovery process. There is no One-Size-Fits-All answer. Even the most basic Rules for Good Writing are pirate rules--that is, guidelines. Too many times, beginners clutch onto the rules presented to them and fail to understand when they don't work for them personally. But hey, that's the first step in becoming a writer: working out what works.
Which is a long way of saying be flexible. YOUR MILEAGE MAY VARY.
Also, I'm not a fan of writing gurus and I certainly don't wish to become one. Teaching is one thing. It's a form of mentoring. That's perfecting fine.
Caveats posted, Dear Reader. Here we go.
Writers spend a majority of their time in their own heads. Pssst! I'll let you in on a secret. A big part of writing is daydreaming. It's true. So, there are two things to keep in mind. The first is, making your mind a place that is comfortable for you to spend time in. That mind sound silly but a lot of the work writers do involves the subconscious. If you can't tap that, you're going to have trouble. If you're subconscious works against you, you guessed it, trouble. Writing is painful enough without that. Knowing yourself is extremely important. Who you are will come out in your writing. Readers and critics will pick up on that. (And others will attempt to and completely miss the mark.) Trust me when I say this, you don't want to be surprised. So, self-examination and even mental health support are, I've found, extremely helpful. Second, TAKE MENTAL BREAKS. EXPERIENCE LIFE OUTSIDE YOUR OWN SKULL. Your family, partners, and coworkers will thank you. Also, if you never observe how human beings interact, you'll never be able to write believable characters that interact with one another let alone a plot. Listen. People watch. Notice details. Films don't count. OMG, have that tattooed somewhere: NOVELS ARE NOT MOVIES. And films are not a substitute for real life observation. Which leads to the next bit.
Life experience is required. Me? I'm a method writer. I need to drive a car fast in order to realistically write a character driving a car fast. I need to fight someone to write combat scenes. That's how I work. How you work may be different. All you may need to do is speak with someone who does these things professionally or as a dedicated hobby. Figure out which you are. In addition, I'd say you need to experience life and what it means to be human before writing about it well. And I'll be honest, that's what stories are at their base. This is why writers cannibalize their own heartbreak, misadventures, losses, terrors, and triumphs. Such things are universal. And your job is to project the universal through the eyes of a point of view character. So, venture into the world. Rollerskate with friends. Hang out. Dance. Go for walks. Have coffee. Social time is not wasted time.
For fuck's sake MOVE. Writers spend a lot of time in stationary positions. This is not good for the human body. Take movement breaks. You're running a marathon, not a sprint. I also suspect that there's some sort of mind-body connection when it comes to creativity. I can't tell you how many times I've gotten stuck on a project and then walked away from the computer only to get barraged with the solution while taking a shower or a long walk. Ask other pros. This is not uncommon. I've discovered I'm a physical person. I need athletic activities. (Which is downright weird since I was always terrible at such things when I was younger. I'm a total klutz. This is just another example of what used to not work for me suddenly did.)
Read. Read. And Read some more. Read other people's works. Learn from other people's mistakes and successes. It's more efficient than making all those mistakes yourself--which is the other option. Also keep in mind that "I can write so much better than [fill in the blank author]." is a newbie statement. Professionals never say this because professionals know that kind of shit is just ego-talk. Every work has its valuable lesson, even if it's "Don't do that." And if it's "Don't do that." be thankful that the author in question took that bullet instead of you. It's a gift of time and energy, frankly.
This isn't by any means a complete list. But it's a few quick thoughts about how to maintain your creative self. I hope you find them useful. If not, I'm perfectly okay with you're ignoring them. What I'm not okay with is you're not finding what does work for you.
Good luck, Dear Reader. Explore your imagination.
 Anyone who tells you otherwise is selling something.
 Rules are, in fact, made to be broken. That's part of being a creative. However, the thing to keep in mind is that only successfully broken rules click with readers, and the only way one learns how to successfully fracture rules is by learning the rules and why they're rules to begin with. If one doesn't understand why a rule was made a rule then one isn't likely to be successful. Even if one, by chance, lucks out into breaking a rule successfully, one won't have the capability to repeat that success. And the thing is, repeating success is vital for professional creatives. It's our damned job.
 Think of it like a map. You need to know the lay of the land and at least one proven path to the destination before you can makeup other routes without getting lost.
 Yes, I took rally racing, fencing, and martial arts lessons. There are boundaries I don't cross--things best left to the imagination, of course. Have some sense.