Torquay business DNA Advertising turned out in colourful costumes featuring yellow characters such as Ali G, Ironman and Tweety-Pie ahead of the annual fundraiser, which officially takes place from March 27 to April 2.
Rowcroft hopes schools, businesses and community groups across South Devon will hold a yellow-themed event for the hospice.
It can be anything from wear yellow day to a custard eating competition.
John Williams, community fundraiser, said: "It's simple, fun and fresh and everyone can join in.
"You can Go Yellow in your lunch hour, after school or for the whole day!."
The campaign raised £8,000 last year to help fund patient care.
For a Go Yellow fundraising pack, contact John on 01803 210846, email john.williams@rowcroft-hospice.org.uk or visit www.rowcrofthospice.org.uk