That's the question, right? So in school we're taught to sketch and sketch and sketch and sketch. When I was an undergrad I had to keep a sketch journal and add a sketch for every day of the semester. (I will admit, on occasion I had to cheat and do several sketches at a time to catch up. Sorry, Professor Atkinson.) When I got to grad school my teacher/mentor thought that was crazy, and he made me do TWO sketches per day. Of course he was an amazing artist and could crank out beautiful sketches at will. At first I had trouble; I wasn't naturally gifted and it was a bit of a chore for me to sketch. Then he taught me to "sketch things that I liked" rather than things I thought I was supposed to be sketching. That did the trick. Suddenly I was interested in my work, and everything became a lot easier. (Or seemed to be easier.)
I kept up the sketching (no, not TWO per day) when I graduated and when I was working as a theatrical designer. I would actually sit in coffee shops around New York City, sketching and getting extremely wired on coffee. But once I started doing faster-paced experiential and live event work my sketching suffered. You just had to work so quickly, and clients rarely wanted to see anything like a sketch. They wanted nice, pretty renderings.
Every now and then I'd get a Producer who would say "oh, you don't have to take the time for a fancy rendering. Just do a quick sketch." But they said that because they didn't have the money to pay for nice renderings, and they thought that hand-sketching was ten times faster. Of course they expected you to turn around amazing "DaVinci-esque" sketches in minutes. I'm not sure where they got the idea that people did this. Maybe they were just delusional. Ah well.
So what do I do these days? Do I sketch or do I jump right into a 3d model of the project? That's the question I'm continually asking myself when I begin my process. And the answer is always different. There are times when I do small thumbnail sketches, just to get on the right track. Other times I will sketch a ground plan in order to get the scale and layout in a good place.
Then there are other times when it's just more productive to go straight into the computer, so that I can work in real scale and manipulate things around like a sculptor. Often I go back to quick-sketching, in order to explore details or see what an alteration might look like.
Sadly I don't hold on to sketches any more. I used to tote around dozens of old sketch books filled with random doodles. I finally had to stop that. Sketches are just a part of my process now; so I don't treat them so preciously. More often than not no one sees the sketches besides myself (although, on occasion, I will email them to Producers while we're hashing things out.) I try to keep my sketching phase at a minimum, though. You can get bogged-down in creating a pretty sketch and forget your priorities. Like every phase of my creative process, I'm always managing my time and balancing when to keep working and when to move ahead. That's something that only experience can teach you.
Ok. . . speaking of "moving ahead". . . enough of that. You get the idea. Thanks for reading!