The radio “Reference Guides” for the three kinds of radios I have at my stations from the Radio Programming page. These are single page print outs that show me how to setup a frequency, repeater offset, and tone in the VFO in case I need to work a repeater I don't have programmed. This is the kind of stuff that's important to know but really easy to forget.
Page 2‒3 of the Nets page using the PDF output command. I also hand wrote the channel numbers for quick cross reference.
I also have my Grid Square taped to my desk. A Grid square is a series alternating pairs of letters and digits like CN89. The more characters are listed, the more precise the location, which is a good way of giving your location to any desired level of resolution and keep any level of privacy you like. With 10 characters, my grid square pretty much pin points my house, but during contests, we usually only give 4 characters, which covers an area of about 5000 km2.