>>125670Use layers, one layer for fills, another for lines.
Use another layer to sketch what you're about to do if it's complicated.
I usually also have one layer above the original where I paint/clone over parts I want removed.
I like using the line/curve tool in
paint.net for making smooth lines. I usually go over the lines at least twice to give them a bit of variation in thickness, but other painting programs have that built in.
If the original is blurry or grainy, as the last step, blur or add noise to the edited lines. You probably have to eyeball it to make it match the original. I also like using the frosted glass filter in
paint.net with some 0-2 pixel maximum radius for a bit of noise and blurring if the original requires it.
You can probably find better advise if you watch a couple of digital inking an painting tutorials on youtube. It's the same thing, really, except you're not creating something from scratch.
Also: If you can see that it's shit yourself, you don't have to post the final result. Consider it an exercise.
