During a long multi-step calculation, how can you "write down" an intermediate result without paper?

Encode it with the Major System — turn the digits into consonant sounds, then a word/image — and park that image, freeing working memory for the live arithmetic.

The Major System maps each digit to a consonant sound, so a number becomes a picturable word. To hold 184 mid-calculation: 1 → D, 8 → V, 4 → R → "Dover" → picture the white cliffs. That image rests in visual/auditory memory while your working memory keeps calculating — the two don't collide. It's the bridge to the Major System module: one turns numbers into pictures, the other does the arithmetic.