>>4919143I try to draw as lightly as possibly in the beginning. Even with pen you can get lines that are barely visible.
I would say that I do mess up and misplace things, but in a drawing like this where there are layers and layers of hatching, if you start out by drawing lightly, the bad lines that you inevitably put down will not end up having a great impact on the overall impression of the drawing, unless maybe they cut across a highlight or something. In the thing i posted here for instance, I placed the chin too low at first, and so there is a barely visible line below where the chin eventually ended up being. But the point is that you don't really notice it and it doesnt in any way interfere with the reading of the face because the background and the actual chin just mostly covers it.
And even if a mistake is in a light area where you can't easily cover it with hatching in the same way, if you've drawn lightly enough, it wont be a problem, because all your work will eventually be put into your hopefully correctly placed elements, and the value and contrast of those will completely overpower any awkward out of place line.
In general I find that when initially placing the elements of the face, you tend to look for downfacing, dark planes anyway, and in those you have more room for error. So in the core shadow of the inside of the eyesocket for instance, if I place it slightly too high or low at first, it doesn't really matter because there is the eyebrow above which also has tone, and there is more shadow below it also. So I have some wiggle room to move it up and down, if that makes sense because that entire area will eventually get more layers of hatching.
I'm not very conscious of my process nor am I used to articulating what I am doing, but I hope that makes sense.
I guess tldr is that you draw lightly and try to only make mistakes in the dark parts that will end up being hatched over anyway :P