Bokeh is influenced mostly by the lens design, aperture, subject distance, background distance, and the background itself. Camera settings other than aperture have little effect on bokeh quality.

To improve it with your current 50mm f/1.8:

• Shoot wider open. At f/1.8 you’ll usually get rounder, smoother blur discs. Stopping down on this lens can make out-of-focus highlights look more polygonal because of the straight aperture blades.
• Get closer to your subject.
• Keep the background farther behind the subject. A larger subject-to-background distance increases blur.
• Choose backgrounds carefully. Small point light sources can give attractive bokeh, while busy patterns, branches, and closely spaced lines often create nervous or distracting blur.

For post-processing, you can selectively blur only the out-of-focus/background areas with a Gaussian blur to make the blur look smoother. Used carefully, this can mimic a softer rendering, but it won’t fully change the lens’s native bokeh character.

So: yes, lens character matters a lot, but shooting wide open, focusing close, increasing background distance, and picking a simpler background can noticeably improve results.