The letter S in braille
dots 2-3-419 of 26⠎
S in braille is dots 2-3-4. S is I plus dot 3.
A capital S has the capital sign, dot 6, in the cell before it: ⠠⠎.
In Grade 2 (contracted) braille, s standing alone as a word means “so”.
Don't mix it up
Now write it yourself
Tap the dots for S, then Enter. On a keyboard, press F D S / J K L together and let go.
Remember it, don't just look it up
S is in Letters K–T. Braille a Day brings it back tomorrow to answer from memory, then again just before you'd forget. Five minutes a day.