Install gutters
If you forget to clean the gutter you will find them damaged after all the leaves and debris and ice got trapped inside the gutter and destroyed it.
In order to avoid these problems and keep the debris out of the gutter you must install a leaf strainer or a gutter guard. Their purpose is to allow only water to flow through the gutter while other particles remain on the outside.
You must clean the gutter and dry it after that in order to apply the sealant on the inner seams of the gutter trough. You should apply just enough sealant as to allow a nice water flow. You risk damaging the sections where the gutter parts connect if you don’t seal the sections well enough because of the water that will corrode them. A hole is probable to appear and the gutter will leak. This is why you must apply sealant.