Should I illustrate my own book?

I'm the world's worst drawer/illustrator/stick-figure creator. That's not false modesty. I mean I totally suck. My book needed illustrations for certain segments. In the preliminary version I just described a couple. As the manuscript got passed back and forth my editor decided more areas could use illustrations.

They had their own art people but I had to do the sketches first. The art folks cleaned them up and sent them back. I suggested a change or two and sent them back again.

In other words, the publisher's art department will probably handle the finished product. But if you can do a half-decent job yourself, and it adds to the book's impact, go for it.

Good luck.

The short answer is "no." It's the publisher's job.

The long answer is it depends on the publisher. As Eraser said, they have art department, illustrators, or they hire freelancers. They have professionals. All you need to do is let them know where you need illustrations. They might like your ideas or your own drawings, but at the end, it's still the publisher's job to decide.

At this stage, I'd say don't worry about illustrations. Just send out the ms.

Another useful thing is to supply references (i.e. photopies of similar diagrams/illustrations, with instructions on what needs changing) for the illustrator to work from. If you're asking for specific photos, it's also useful to provide photocopied references, as sometimes the picture researcher may be able to use the same photo. For both photo and illustration references, it's important to also photocopy the acknowledgements page in the book.

If you're writing on spec, rather than to commission, I would suggest for the moment, putting in figure numbers and making notes for yourself on what pictures you want and need. Many publishers will have specific guidelines on what authors need to provide (and how to do so) in terms of artwork and photos. You can then ensure you do it the right way for the specific publisher when the time comes.

(If you're writing to a commission, then just follow the guidelines exactly.)