Don't try to clean your gutters by flushing them with a garden hose. You'll probably end up clogging the downspout and making a big mess. Instead, clean the gutters when they're dry, and use the hose to flush out any remaining debris. Check for damage or missing parts as you clean the gutters. At the bottom of your downspout there should be an elbow that directs water away from the house.
Elbows are inexpensive and come in several colors.
The support piece provides a permanent access point to your roof and is fastened to the wood underneath the roof using galvanized deck screws. It can also be mounted directly to the gutter. The stabilizer's wide arms help prevent the ladder from shifting side to side.