I do this in a very old fashioned way.
1.
Put on something to listen to. Either a documentary or somebody talking about an interesting subject, or some music. When drawing I get the most out of old (and some new) electronic music. Jean Michel Jarre, Tangerine Dream, Kraftwerk and related artists.
2.
Then I (almost) always starts with making small thumbnails of the whole thing. I do that 3 or 4 times before I start drawing, changing almost everything. And then I just start drawing the final thing. One page at the time. And here the layout of the page has a habit of changing a lot again.
3.
I always draw on the same kind of paper (Daler Rowney Bristol), and sketch with the same mechanical pencil (0.7 size). And always sketch out a grid based on phi in each panel. This makes it a lot easier to place everything inside the panels.Then I ink the panel borders. Always using the same nib, Tachikawa No. 120 with Speedball ink.
4.
Start collecting all reference material. Mostly poses, old cars, sometimes cities and sometimes animals.
5.
Start sketching on the actual page. Eveything from now on happens on the same piece of paper. The horisontal lines first, then characters, then everything in the backgrounds that needs to be sketched in.
6.
Then my favorite part which is inking the outlines and eventual hatching. I often go back and forth between inking and sketching and don't always make the pencils too defined. It makes me more focused and makes the whole thing look more spontaneous. I use one nib for everything inside the panels. It is called the G-Pen Zebra. It is very precise and lasts for ages. ANd more Speedball ink.
7.
Then the next step is to erase all the pencil lines and try to hide all mistakes. White gouache paint works good here. And then fill in all the bigger solid black spaces with a brush. It's a 2 sized Daler Rowney. Here I like to use Winsor & Newton India ink.
8.
Then of course the whole thing has to be scanned into bmp and 600dpi. And some quick cleanup is needed. Now my least favorite part is coming, the coloring. I've never liked it. I hardly ever touched my coloring books when I was a kid. But it is needed to get the look that I want. It is a very simple process. Base colors and gradients, then shadows, then highlights. Sometimes I just do base colors, gradients and highlights. And sometimes I just skip the coloring.
9.
Then there is a really tedious process of looking over everything to make sure I didn't overlook anything. And then do steps 3-8 over and over again until the whole thing is finished.
10.
The final step is either to post it online or start nagging at the publishers.