Oh, I forgot to mention. When I memo corners (for pochmann), I use visual but I also say the letters of the side that the sticker is on while tapping the pieces and remember that string of letters by auditory memory. For example, I might end up with R-R-L-F-B or something and then I just have to remember the order of the pieces. Using this method, my corner memo is by far the faster part of my memo and usually doesn't take more than 15 seconds.