I can honestly say I never fall short of being creative. Not that I'm the most creative person out there - But I've come across numerous ways to promote creativity - some I've researched over the years and others I have stumbled upon or created out of desperation. Because there's two things that get stuff done in the world. That's inspiration or desperation. Consider these tips for your inspirations and bookmark them for all your future creative blocks.
Question your subconscious
It works pretty simple. Ask aloud or within your own mind and let the hidden power of your subconscious work for you. Just as you may be trying to think of the name of a song, or an actor in a movie. It may be on the tip of your tongue and you think "what is the name of so-so? I can almost see their name" Then hours later the name might instantly pop in your head. That is because your subconscious mind never stopped working for you. Use this technique to ask questions like "How am I becoming so creative?" "Why are my ideas getting better and better?" If you've ever heard of the term Affirmations, these are referred to as Afformations. And they really do work. https://afformations.com/tas
Repetitive movements
One of best perks of a warehouse job I use to have was the repetitious nature of it. I would strip corrugated boxes of their excess paper and fold them into cartons. And I would do this thousands of times a day. My hands got to the point where every movement was synchronized and it looked like a folding ballet. The normal person attempting this would have a few papercuts in mere minutes. What this allowed for is incredibly creative moments. Almost like you leave part of your thinking to do all the mechanical movements for you and all you're left with is creativeness. You could do this on your own by even folding laundry believe it or not - which brings me to my next point
Even if you have a washer/dryer - take your clothes to the laundromat
Being out of your element and performing a task such as washing/drying/folding clothes will spark curiosity within. You would be surprised at how interesting your thoughts become to the sound of washers and dryers and the people without them.
Slow your breathing
This works because you force an unconscious act into your consciousness. This helps keep your attention on your breathing while letting creativity flow. Pay attention to the breath as you consciously slow it down. While seated or lying down, count all the breaths. Inhale for 4 seconds, hold for 4 seconds, exhale for 4 seconds, then wait for 4 seconds. When your thoughts drift from the counting, just bring them back. As you begin to do this and feel more relaxed you can direct your thoughts to your work and it should be easier to imagine and create the good stuff.
Listen to instrumental music
We all have heard this before but no everyone does it. Although many proclaim that music with vocals does the same for them. It is also important to not have to acknowledge any lyrics at all. The music itself drives the mood of your thoughts. Many writers claim when writing a certain piece of work, they may listen to the same song, over and over again to catch the mood of what inspired them.
Just start writing method
Forcing yourself to write doesn't make sense but you should definitely try it. No deleting, just write exactly what you're thinking and you'll work into a flow within the first couple paragraphs. It will sound silly but it will work, trust me, eventually you'll be able to write extensively about whatever subject you'd like.
Go for a walk
Even if you have somewhere you often go to walk, find someplace more quiet, or take a path you never have before. All these little nuances of direction help snap you out of creative blocks.
Re-watch your most watched or favorite movie and look for things in the background you wouldn't normally notice
To me it would either be The Matrix or Home Alone. Paying attention to the background characters or whatever is not the subject of the shot will help tweak the creative juices. Subconsciously, it reminds you to find differences in your norm. You may even end up writing about a new topic or working on something you'd never see yourself doing before. And if anyone else is a Matrix fan, enjoy this 
Body Scan Meditation
This is best when done lying down. But be careful- it may put you to sleep, which might not be a bad thing. While lying down, begin to acknowledge the different parts of your body. Actually notice how they feel. Starting with the feet, and if it helps just say in your head "I am noticing my toes, I am noticing the bottoms of my feet, I am noticing the tops of my feet.. etc" As you do this become aware of the different parts and you'll begin to notice that when you do this, those parts relax. We carry so much tension in our bodies and never recognize this. But slowly do this and work your way up to the top of your head. Or for a directed version, try this with headphones
Start from where you, close your eyes, and imagine the rest of your day
Now there are MANY important benefits from this that I won't go into..because they will format your life, for the better that is. But it's a great way to get creative and even become enthusiastic about your creations. They will spawn new ideas and they'll not only be some of your best work, you'll never believe you had it in you. Now if only public education didn't cut us off from our natural tendencies we would always be in a creative flow.
Take a shower, preferably at not your normal temperature
There's something about showering that sets the mind free. Maybe it's because you've done it thousands of times, hopefully. Maybe it's a subconscious side effect of the water cleansing not just your body but your mind. But most people would agree that they've had at lest one, if not many, "ah-ha" moments in the shower. The mind is allowed to run free as the body goes through its routines. Rinsing skin, washing hair, and starring at the walls. My wife heard me talk about my great ideas lost down the drain so many times, that she bought me aqua notes. More convenient than you'd think. https://www.amazon.com/Aqua-Notes-Waterproof-Notepad-Mountable/dp/B003W09LTQ
If you're a cook, cook with several ingredients you've never used before
There's a common theme in a lot of these Tips, and that is to get into the habit of stepping out of your normal day. The normal routine where thoughts come and go and you don't even realize you have no control over them. It's not only that you do, you can convince yourself that you can actually have great thoughts, all the time. Changing the little things begin to have a major impact on the way you think.
Turn on your GPS and go for a drive without a specific direction and travel down some roads you've never been on before
This works great for two main reasons. One is for the reason I just mentioned of stepping out of your normal routine. And two, because you might actually come across something interesting to think about. Think of it like the movie "The Truman Show" When Truman begins to realize something is wrong with his world, it's only when he changes his everyday routine that he starts to notice things differently. I won't ruin anymore of the movie because it's surprisingly really good. Go give it a watch if you haven't before.
If you normally write via keyboard/computer use pen and paper
My wife swears by handwriting. She is a blogger(before joining Steemit) and she always writes her blogs and her ideas on paper before using the computer. She calls it her meditation. And I would have to agree that it works really well for her. If my handwriting was better I'm sure I would prefer it to. I have been caught handwriting though if I'm out somewhere hiking or backpacking and I don't have access to a computer.