There are many available resources that explain the importance of practicing “clean drain dry” and show how to do it.
The graphic below shows all of the places on your boat that you should clean, drain, and dry.
The three-minute video at the link below, produced by Texas Parks and Wildlife, provides a funny and thorough overview of “clean drain dry."
How to Clean, Drain, and Dry Your Boat
Other videos showing examples are linked in the reference section.
For more information on “clean drain dry” best practices, consult the following website:
What Can You Do? Practice Clean, Drain, and Dry https://www2.gov.bc.ca/gov/content/invasive-mussels/what-can-you-do