vinyl decals?

what is the difference between vinyl and waterslide decals? Is there a different way to apply them?

Waterslide decals are way smaller in thickness compared to most adhesive backed vinyl. That is a main difference. There adhesive properties are different too. Vinyl is a cut and apply type thing. You can use soapy water to arrange it, but mostly stick and go. It leaves a definite edge on a 1:1 car, and would leave a huge edge on a model. When the glue from vinyl adheres for a while it can become very tacky to the point where it will take off paint. I have seen this on a real car. I would not ever go that route, but that is me.

To apply water decals you simply cut out the one you need/want, then dip it in a small container with luke warm water for a bit until the backing paper is soaked and the decal can slide off. Then you apply it to where you need it. I load a brush up with water to move it until I am satisfied with the location. After that I dab a paper towel on a bit of and edge and it absorbs the remaining water. Then you either let it stay until dry, or add softening agents to it to help it conform to the surface. Pretty cut and dry to do.

Disclaimer - I know this is not a text book definition, lol.