You might already know this, but you should see:

My method of mimicing the style would be by drawing whatever I want in real life (With a vauge sort of World of Goo), then adding details in photoshop. If you don't have photoshop, use https://pixlr.com/editor/ . It may not be good as Photoshop, but it's free (and online).

Does that help?

Well, it helps a little bit. I'm thinking of buying a new computer this summer.

That's what I can make:

View post on imgur.com

That looks nice! If I were you, though, I'd style most of the levels like that, so there wouldn't be much of a change in what the levels look like.

the only thing what I would really like to add is shading, but I don't know and my pc is slow

Use the filter/vignette tool on the website I recommended.

Okay, I will try now

did it work?