While thinking about Keys, the Circle of Fifths, Scales, and which keys have which sharps and/or flats in them, and how to remember which is which, I found a way to remember it visually. It’s not revolutionary but maybe others could find it interesting. Only major keys are considered here.
The most used (and most useful for guitarists) part of the Circle of Fifths goes C G D A E – each new key going up from I to V of the previous key, with each key acquiring an extra Sharp in it.
The Sharps are added to each new key in order (added to the C chord which has no sharps or flats) They are added in this order as you go around the Circle of Fifths :
F# C# G# D# so that the Keys (and the Major Scales) have
Key of
Cmajor - no sharps or flats
Gmajor - has F# in it instead of plain F natural (one sharp)
Dmajor - has F# and C# also, instead of C natural (2 sharps)
Amajor – has F#, C#, and G# also, instead of G natural (3 sharps)
Emajor – has F#, C#, G#, and D# also, instead of D natural (4 sharps)
So I thought of a way to remember this visually on the fretboard.
If you place your fingers x x 1 1 2 2 on the top 4 strings.
which in tabs is
-------2---- F# for the Key of Gmajor
-------2---- C# added for the key of Dmajor
--1----------G# added for the key of Amajor
--1------- -- D# added for the key of Emajor
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From the top string going down you have a visual ‘map’ of the sharps in the order which corresponds the Sharps that are added to the Keys of The Circle of Fifths. – and also the frets on the fretboard that you play when you play each Scale.
Thinking of ways to remember the names of the notes (and not just the places on the fretboard) for example
Father Christmas Goes Down And Eats Biscuits
and for the sharps
Free Chips Give Delight
I recommend people come up with their own personalised ways to remember. Any useful and memorable suggestions could be posted on this thread. The only rule is Keep It Family Friendly please.

One good thing about music is that when it hits you, you feel no pain - Bob Marley