Last time I asked this question I got told to just draw more.

Since that never helped me I just gave up on any kind of art that doesn't let me refine my lines in the finishing stage.

>>2412990
try looking up some of the exercises from scott robertson. he has some pretty solid line work.

Just grab a piece of paper and do it.

At least once a day and whenever I start drawing, I always fill up a page or two with just circles and lines. I'll also usually try to do some rough shading to turn the circles into spheres and I'll try to draw additional lines parallel to the first lines. I wouldn't spend more than five to ten minutes on it, but I personally find that it helps warm up my arm and improve the crispness of my marks. Just make sure you're drawing things at a variety of sizes and that you get your arm, wrist, and fingers involved, otherwise it'll be a waste of time.

>>2413552
See, there it is.

>>2413538
Not line art related, but he's a digital painting master.

https://www.youtube.com/watch?v=8i2ksDRapO4

>>2412990
What's this and what's its use?