Some graphics are best installed using this wet method, like anything we print on clear. If your boat graphics are printed on white vinyl we DONT want to use a wet method as that material uses air channel technology for bubble-free installs. See the Hinge Method or the Butterfly Method for the graphics printed on white. Water in those channels defeats their purpose.
However, if your graphic has a foil overlay, like a gold or silver outline, or is printed on clear to take advantage of a soft drop shadow that blends into your hull color, these call for wet applications. In a wet application, the water prevents the vinyl from sticking right away and allows one to reposition it by sliding the graphic around. When registering a second layer, this is particularly helpful. Check out this video for example.
We use Rapidtac diluted 50% with water, but really you can get away with just adding a few drops of dish soap to a quart spray bottle, just enough to break the surface tension of water. It’s important to have a good plastic squeegee to squeeze the water out and apply enough pressure to get the graphic mounted without bubbles. We sell those with a kit that includes a spray bottle with Rapidtac if you’re interested.