Written out
Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.
The step pattern
GWAWBWC♯WD♯WE♯WG
What is true of it
G whole tone is G, A, B, C♯, D♯ and E♯, and back to G.
Its steps are W – W – W – W – W – W, where W is a whole step and H a half.
Across the first twelve frets of the ukulele its notes fall in 26 places, which is what makes a scale a shape rather than a list.
Chords made only of these notes
Found by testing every chord in the catalogue against these 6 sounds, not chosen.