A single word for "to paint and/or draw"?

Solution 1:

There is no single word that can directly replace paint/draw in a sentence. Painting and drawing are two distinct activities. In fact, artists who work in 2D do not only paint or draw. They make prints, do collages and much more. (I say this as someone who was once an artist.) Given your example, some options might be:

• Did you work in the studio today?
• Did you do any art today?

If the artist in question only paints or draws on a regular basis, then nothing beats

• Did you paint or draw today?

Another option:

• Are you still working on that piece?

Solution 2:

How about to render?

e.g.

To render in ink

"He rendered the portrait in watercolor"

Solution 3:

Although somewhat generic, create is a word you could use. You will have to rephrase the sentence into:

The artist created a picture of a horse.

Solution 4:

Perhaps...to illustrate?

"The artist illustrated a horse."