How hard could it be to use your imagination without a single image, symbol or visual representation of any kind?
Choose a sense that isn't sight and pick something with the least amount of representation to a visual cue.
The sense of smell may be the hardest despite initial belief concerning smell.
Because it is impossible to think without the memory of some visual cue of any kind, including darkness, do not focus on not having sight but rather being in a dark room. Keep it that way, the absence of visual representation like a shapeless void.
Push out everything you can that reminds you of anything in this world which your mind can associate an image to. Words, people, places, sounds that come from a physical instrument, smells that come from an object. Truly empty your head of the thought that carries with it a shape, a color a distinction that you can trace.
Don't play games with yourself by imagining nothing.
Don't convince yourself the void is something of itself.
That's the trick with the imagination after all, it creates.
You shouldn't know anything about vibrancy, hues, sizes or shapes. That's a clear representation in your head even if your physical sense of sight is overpowering your imagination. You can know things about density, weight, fluidity, or some representation of a physical feeling like butterflies in the stomach or nausea or the feeling of floating or falling. But to attach a representation to it that's is associated with a visual cue is to bring forth the imagination in forms of images even if it is in darkness.
Be creative by losing halting your need to think with images.
If you can't force your mind to think it, tell it out loud. Pick something that is without visual form. There are plenty of things in this universe that the human mind can sense without the eyes just as things that exist that the eyes can not sense. Blind your imaging process with the searing brightness of your will and look not with your eyes anymore to extend the rest of your senses outwards.
Most people will say they don't believe what they don't see.
Even a blind man can sense more than those who can see.
You can't be sure you are fully using your major senses.
If you can manage to accomplish this at all for even a moment, try to do it for longer than what you achieved. Use more of the non-visual cues to accomplish this. Set your goal to achieve a state of mind that is void of visual representation even if your imagination runs wild with a plethora of other things. Seek a state of control and even a state of comfort in it if you do not have one.
Now try it with your eyes open.
