Diminished scales are 8-note scales and they are symmetrical. There are only 2 (enharmonically) diminished scales: One is based on a hale/whole step formula; the other based on a whole/half formula.
Eight note scales are easy to practice with a metronome. I have found that the symmetrical nature of chords or scales makes fingering easier on guitar or piano, possibly other instruments.
The half/whole type of diminished scale goes well over a dominant 7th chord; the whole/half type fits well when played over a diminished or half-diminished chord, e.g., a 2-5-1 in a minor key.
In the chart below, the 1st 4 bars are simply the C diminished scale (half/whole) ascending and descending.