For anyone who's ever been curious to how Takahashi works, here's a good place to start. This is by no means a definitive guide, but rather focuses on certain interesting aspects of her creative process.
If you'd read "kemo kobiru no nikki" you'd know that Takahashi works out of home and deals with her company Shogakukan primarily through her editor. She lives with her two assistants Makiko Nakano and Kuniko Saito who help her with all the various tasks that make up the creation of a manga. Occasionally she'll get additional help when things are particularly tight. Takahashi is still the force behind the comics, but it shouldn't be underestimated how much her assistants have contributed to her series through the years. She certainly wouldn't have been able to do a weekly series or even think of putting out Urusei Yatsura and Maison Ikkoku simultaneously without them.
Now let's take a look at some of the aspects of how Takahashi creates her manga.
Every week Takahashi and her staff meet with their editor to discuss the upcoming story. While she may have some of it planned in advance (especially in the case of story arcs), Takahashi tends to work out the details of the stories on a week-by-week basis. That spontanaety is why some of her manga have such unexpected twists and clever ideas. This picture depicts what such a brainstorm session looks like. (Notice how everyone is pretending to concentrate on the job at hand, but are actually watching TV).
As the following picture depicts, after an outline of the story and gags are agreed upon, Takahashi and her assistants start creating a pencil draft which provides a rough in pencil of the entire comic story. Takahashi draws up the story while her assistants help with more menial things such as drawing the boxes (FYI, the editor's just hanging around with nothing to do and the women are working but their minds are on food, sleep and booze).
Below are some sample images that will show you exactly what Takahashi's roughs look like. These are from the story is from the "Shashin no naka no onna" (The Girl in the Photo), which is a story focusing on Kitsune and Shinobu.
As you can see the drawings are very sketchy and lack detail, but at this point it could be considered a complete comic. It has all the important imagery and dialogue and thus could be read from beginning to end like any comic. All it lacks is refinement. Even so, this stage is is only the beginning and there are still several days of illustrative, design and typography work left to be done. But now that they have this rough, the creative aspect is mostly over with and it's all about technique from then on. It's generally at the post-rough stage that the assistants step up their efforts to handle much of the re-drawing and type work along with Takahashi.
Since the final draft stage is pretty self-explainatory (just trace and redraw in pen), let's go a bit off track here to look Takahashi's own drawing technique with those beautiful watercolour illustrations that are found on the covers and insert pages of her books. Takahashi's been drawing in that medium for a long time, and so she has a very specific system to how she creates an illustration. This page will take you step by step through how she drew the illustration found on the back of tankoban volume 12. Click on the image below to begin. (pops-up in a new window)
Okay, maybe not. But you can at least draw a simple Lum picture. Here's a "how to draw Lum" sheet presented to Shonen Sunday readers by Takahashi. While it doesn't reveal all those trade secrets that'll make you into a world-reknowned comic artist, I'm sure some people will find this a fun little excercise. It's in Japanese, but the pictures are pretty self-explainitory. Click on the picture to view.