Using stick on dots for parking

I am trying to find instructions for sticking small dots on the RV to assist in parking and knowing where the road edge is. We learned this when we bought our first MH at Lazy Days in the class we took but have a new RV and I want to do this again..it was really helpful. I recall we had ine on the low edge if the windshield and one on drivers side...can anyone help me find the directions or video.
Pat