There are as many ways to fight writer's block as there are writers. But for me, here are the top 5.
1) Read or watch something completely different. You can try to enjoy it (AND SHOULD). So if you don't read mysteries, read one. If you don't read romance novels, read one. If you don't read hard sci-fi, find a good books and read it. This takes you outside your comfort zone. It also gives you a different point of view. If you can, you should then analyze it. What was good about it? What made it good or bad? What were the neat turns of phrase in the work? What visually worked for you (even in a book, there are visual passages)? Sometimes I try to duplicate some of it... I watched a bunch of old (bad) kung fu movies from China. I found myself thinking about kung fu/ martial arts rules. I saw how description would work for things. I saw how scenes could be combined and how characters should be motivated. It can expand your world. I have done the same with Romance Novels, mysteries, and light urban fantasy.
2) Drop all your current projects and adopt a new one. I mean it. Let them go. Either find something from your old notes/ notebooks/ manuscripts so embarassing they shold be burned, OR do something new (see #1) A new project with new expectations might be totally free of what is blocking you. You will find yourself writing again. Or if nothing else, you can fix some old stuff. After a while go back to your formerly current project and see if you can write on it now.
3) Fic: So, watch half a TV episode of a show you like. Now,write the 2nd half. Do not duplicate the original episode, but find your own way. Read a book (preferably one you are familiar with, but not required) for the first few chapters. Then start writing the rest. Now remember, nobody is probably going to read this, so just do it and have fun. I try to duplicate the writing style of the author (or at least their "voice").
2 and 3 are good exercises to free you mind. These are not things you are going to publish or anything... they are just writing exercises toget you going.....
4) 5 minute writing exercise. Take a piece of paper and pen (keyboard if you are more familiar) and get ready. Get a timer and set it for five minutes. Without thinking about it too hard, just write the first things in your head. If nothing comes to mind, write/ type nothing. If you talk to yourself, write that down. If you have a profound or profane thought, write it down. Write as fast as you can for 5 minutes. You can not pause to think. You must write as fast as you can. Push yourself. If you notice you have stopped, start up. This helps you warm up to writing. It will also let you have a dialog with yourself. Why am I blocked? Why do I hate my job? Why am I so stressed? These topics always pop up in these exercises.
5) Never ever stop writing. Your goal is a minimum of 500 words a day. Do I care on what topic or project? No. Creativity and writing are skills that needs to be exercised. The more you write, the more you can write. Practce. Practice. Practice. Some great novelist said, "Your first 100,000 words are crap." So get them out of your system. Write essays, write blogs, write emails to friends and family, write Strolen Posts, write scroll additions, or just write anything. Write and write as well as you can.
Eventually your minimum word count should increase. When I am in the groove, my minimum count is about 1500 words of posts, emails, and notes on game projects, a day. Okay, since I am on like 6 sites, nobody realizes the volume I am puting out. That is also okay, because some of it is utter crap.
One last piece of advice: Writing crap is okay. Let people see your crap. You are not Hemmingway, Tolkien, etc, etc (yet). It does not have to be perfect. At least your wrote. Sometimes the crap turns out pretty good. Unless you write and let others see it, you will never see how good it can be. (Just because you think it is crap, does not mean it really is crap. I have a bunch of highly rated subs that I think are total crap. However, everyone thinks they are wonderful. They do not know what I think they should of been and included. ) So write. Eventually the crap will fade away and good things will come out.