I can't even begin to count the number of times I have heard the phrase"I can't draw!" I would like to remark that I have never heard this from a child. At what point does the switch flip in our heads that makes us believe that the instant we try something new, it needs to be perfect. Why is it that so many adults are afraid to do something new, to be on the brink of discovery, and ready to make "mistakes" along the road.
When I was teaching drawing, I would always hear "but I can't even draw a straight line!"
Why do you think we have rulers? A straight line is not a very interesting line - all it speaks is"I have a ruler" or "I can behave as a ruler" ...yawn.
So stretch yourself, be alone if you have to, draw a wobbly line. Look at it. Open your imagination. What have you started? Perhaps you are looking at the edge of a distant forest in that line. Perhaps it is as fine as the grain in an old oak table. It is potential. It is a starting point. It is the wandering of your mind.
Of course, with any art, work and study improves our skill. There are many elements to consider with each fresh sheet of paper: colour, line quality, use of media, negative space, composition. I'll stop there.
So grown-ups, I hate to break it to you but "can't" just don't cut it. You may want to rephrase:
"I don't want to draw."
"I'm afraid someone will laugh at me if I try" (so, do it anyway)
"I don't want to put the time in to learn something new."
Rest assured, if you want to, you can, and it could bring you so much satisfaction. Remember how it feels to do something just for you - something that relaxes you, gives you a break from the work-a-day monotony, brings you a little joy.
Take a class if you want or just sit down with a piece of paper and a pencil.
Of course, at first, everybody wants to draw something and reproduce that something exactly as they see it. You can get there when you learn to see. It takes time. It takes practice but you can get there. The really great thing is, once you learn to draw one thing and grasp the basic skills that it took to draw that one thing, it won't be too long before you can draw anything. After that you can bend the rules if you want - play with it. I recommend "playing" all along the way. You'll learn more and it will be more fun. Play with your materials. Play with your imagination. Don't be afraid to crumple up your page and start again. Keep your work and look back at it. Look for change. Experiment. Be a scientist. It doesn't matter if you "mess up". Do it again. Whatever you created, you can do again - maybe different, maybe better.
Do it for you. It will change your perspective. You will find that you see things differently. You will simply see more. The imagination is a gift, the drawing is a desire, the brilliance of it is practice and skill.