I've found the best way to empty your mind is simply to stop focusing on emptying the mind. The more you grasp for it, the more elusive it gets. Stop expending so much effort, the easier becomes. But that makes it seem easier than it actually is.

To go in more depth: I used to try meditating by forcing out any thoughts that came or focusing on not thinking. This was not completely ineffective, it still calmed me a bit, but it made meditation frustrating and something I felt I couldn't do. So. I read more and eventually came to the method I use when I do bother to meditate. Basically a combo of focusing on breath and counting said breaths. If a thought emerges, I acknowledge it, then move on without giving it my attention. Forcing yourself not to think is giving the thoughts attention. You might check our Thich Nhat Hanh's "The Miracle of Mindfulness"; while I read a few others works previous that helped me better understand Zen and improve at meditating, his is probably the best simple practical guide. At least in a certain Buddhist style. There are many different ways to meditate in many different traditions, not all of which use this concept of emptying.

Art is one means of emptying the mind, but I would look to what the Zen artists do in their brush paintings or the Surrealists in their automatism. Artwork focused on achieving a certain goal, specifically an intentional structure pre-plotted and then filled out, is not quite as good for this practice. What has always felt most "Zen" to me:  filling large spaces with small repetitive marks, simply marking and "feeling" the line or expression, filling out forms with no sense of what they might become, having no preconceptions of what the piece might look like.

Well, perhaps I can help you.

The topic ... philosophy - I would say yes.
Even religion outside Buddhism. I use it to detach myself from material necessities and to improve myself to sit in God's Light some day.
And last but not least I use it for my art.

Here, I have a link how to clear your mind which is basics for so many other things (that is why the essay is titled Past Life Regression - but first I described how to clear your mind). Perhaps it could be of some help to you:
Past Life Regression

I use deep meditation to empty my mind, mostly transcendental (as you might see from my link).

No, I have never worked out emptying my mind by making art, but the other way round. I empty my mind to make art. That prevented me from having those so-called art blocks and I can jump into contests just one day before deadline. Not only because of the contents of my works but mostly because of the way I create art, I call myself a spiritual artist.

For example, when I meditate on a given topic, several pictures arrive in front of my inner eye and I just note them down - that is why some people say that I write in pictures.

I have been meditating since I was a child, as my parents are that way. I never was, and still am not, very good at 'emptying my mind.' The phrase never really made a lot of sense to me, to be honest. The way I typically quiet my mind (a phrase that sits better with me tbh) is through focus. So mindfulness meditation practice is one way, but yes getting hyper focused in the process of creation is another (similar) one. My art requires a lot of thoughtless repetitive motion - so I get caught up in the experience of the process of creating. I find the process of creating my art to be rather meditative and thats in fact how I started doing it. I made my first beaded bouquet in my spare time when I worked full time, just for the mental health benefits that the exercise of creating it provided.

A friend, who also did meditation as a child, they had her sit and focus on the image of a candle, including quite literally. They would sit her in front of a lit candle and have her focus on the light, on the shapes of it flickering, etc. That seems like a nice, simple, effective method of getting in that zone.

When I am meditating, no 'forms' appear to me. I never think visually. I am unable to, I never have been able to.

Mostly I just get calmer.

Meditate on grayness, oneness, silence, and detachment for several minutes.
(several people have already given good meditative advice already)
If you ask because stillness of mind gets in the way of art, I can understand.
It is hard to imagine being infinitely creative no matter what.
But we are, I am, and you can be.
So start sketching and don't worry.

Why do you want to make art with an 'empty' mind? Whose idea is that?

I usually CLEAR myself spiritually through the messing of my E-Meter.

IMO, it's not about emptying your mind; rather it's about recognizing the emptiness of the forms which arise in your mind, which leads to a sense of freedom. Just as we can break any physical object down to its elements, we can do the same with mental forms, which leads to detachment.

Hollow-point, small cal.

While large cal is technically better for doing actual damage, and you will be at point blank for obvious reasons, the fact remains that handling and aiming the damned thing is probably too much to ask, for someone so terrified of life as to be asking questions like this.

If the book I read about Buddhist artwork is any indication... 

then you've just insulted someone. 

Meditation is about learning to be in the present moment-- don't think about the past or the future-- but about the present. Concentrating on breathing helps that. There are also mantras. But really you just have to remember the main principle of mindfulness-- that too much thought on the past fills you with grief, while too much worrying about the future creates worry, and thoughts on the present fill you with contentment. 

Good practice for a stressful life, if you're patient enough. You might realize for the first time how boring life is. If you're really an artist, of course you're patient enough. 

Don't empty your mind.

I don't empty my head. I just let myself wonder without worrying.

Ketamine? 

I agree with da1withthelongestname above - I walk as well.

Initially I started for exercise as I'm training for an upcoming hike, but I walk in the same place back and forth (hill training). I'm finding it's quite meditative.

When I start walking and once I get trudging along, I'm just in the present. Not thinking about the day ahead of me, not thinking about the days passed. I just observe the ground under my feet, and the birds and other creatures that are on the path (i.e. no headphones or other distractions).

Once I get home, then I can focus on the day, or let thoughts come back.

i've never been able to empty my mind. i work with a full mind.

When I clear my mind of all things, I am emptying all thoughts I have about everything - a blank canvas, to be painted with new thoughts. I try to think about things I normally don't think about - to avoid simply repainting what was already there.

I mostly use this to create abstract/expressive/impressionism type of art - or stream of consciousness / beat literature / poetry writing.

play vidya games it helps me to clear a head

I can never empty my mind. I'm always worrying about something or thinking up possible storylines for a comic or ideas for a new art piece. The only time my mind is at piece is when I'm sleeping and even then it's not completely empty because of dreams. o.o

not an empty mind, but a free mind will make you creative.