Just for this purpose I put a small piece of white tape on the bottom center of my rear view mirror, a small piece of white tape on the bottom center of my rear sliding window and a small piece of white tape on the forward facing, center, and upper portion of my hitch. All I do is line up all pieces of tape while looking in my rear view mirror and slowly back up toward the hitch. I can usually back within a few inches of the connect point on the first try. This simple method is like lining up the sights on a rifle: align the front and rear sights (mirror and back window) to the target (white tape on hitch). If you can not see your hitch, try putting the tape on the part of your pin box that you can see from the driver seat. You asked for simple ideas, so here is what works for me.
Lakeside