The guide, produced in collaboration with marine users, also encouraged people to report invasive non-native species they see in the water or on the shoreline.
Julia Henney, the States’ senior natural environment officer, said there were already many invasive marine species in Guernsey, including Japanese wireweed.
She said the guidance aimed to help promote best practice as “once these species get here, they are almost always impossible to remove”.
“There are hundreds more potentially invasive species on the horizon which could cause significant environmental, social and economic impacts if they were to enter our waters,” Henney said.