A realistic myopia look is hard to fake convincingly in post. Strong nearsightedness is mainly an optical focusing problem, so the best approach is to create it in-camera.

Try this:

• Use manual focus and set the lens to focus very close, leaving the rest of the scene out of focus.
• A macro lens or extension tube can help if you need a very short focusing distance.
• Aperture matters too, because pupil size affects the blur. A wider pupil / wider aperture gives stronger blur and bokeh-like highlights.

One answer suggests estimating the unaided focus distance from diopters as:

• focus distance ≈ 1 meter ÷ diopters So a very strong prescription would mean focusing only a few centimeters away.

Post-processing blur usually looks wrong because it doesn’t reproduce real optical effects like highlight blooming and bokeh. If you still want to edit, Photoshop-style combinations of desaturation, minimum/maximum filters, gaussian blur, soft light blending, and slight channel adjustments can create a stylized approximation—but not a truly accurate simulation.

So: for realism, shoot it optically with close manual focus (and possibly extension tubes or macro gear); use post only for fine-tuning.