Do you struggle to quickly work out what key harmonica you need when the key of the song is mentioned? If you play cross harp (second position), then here is my top tip to know instantly what key harp you need.
It's very straightforward. Simply use the initials of famous people or characters to work out what harp key you need; the initial of the first name is the song key, and the initial of the surname is the harp key required. Please note that I live in the UK, so some of these names may be unfamiliar if you live elsewhere - but please bear with me!
If the song is in G then you can use the initials of ladies' favourite George Clooney, although I prefer to use the actor George Cole to tell me that I need a C harp. He played the character Arthur Daley. Following the same theme, I use Billy Elliot, Colin Firth, David Ginola, Eamonn Andrews and Frank B-bruno.
In the unlikely event you are being asked to play in a Flat or sharp key, just simply add the word sharp/flat to the names, e.g. G# will require a C# harp (This works pretty much for all but one or two keys).
Of course, you can choose your own names (especially if you don't live in the UK) - www.peoplebyinitials.com may give you a head start.