They don't make cold calls, they make informed calls. Designers are enthusiastic. Their enthusiasm can be contagious. Designers have portfolios and give presentations. Designers tell the stories behind the publications in their portfolios, explaining the challenges they faced and how they resolved them.
Designers leave samples behind when they are done with a presentation or meeting with a client.
Designers ask their clients for referrals. According to Hutter, who currently manages a publications department, she often receives calls from designers, whereas over the last 6 months she has received only one call from a writer.