Typing on old manual typewriters required more physical effort than on a modern keyboard.
Each new sheet of paper had to be placed between the rollers and wound into position by hand using roller knobs at either side of the typewriter.
When typing, substantial pressure had to be applied to a key because it had to force a metal print-head up to press hard onto an inked typewriter ribbon, to make an impression on the paper.
At the end of each typed line, the typist had to move her left hand away from the keyboard to pull a large lever to return the rollers and paper to the beginning of the next line, as the rollers and paper had moved along as she typed.
Then, at the end of every page, the rollers needed to be wound back to release the paper.
Every typewriter had a fixed typeface with two characters on each print-head - one upper case and the other lower case. There were keys at both sides of the keyboard to raise the rollers so that the upper case character hit the ribbon.
Sometimes, if the typing was too fast or more than one key got pressed at the same time, the printheads would lock and need to be disentangled by hand.
The standard size for paper was called foolscap. It was slightly taller than A4 as can be recognised from the photo below.
It was difficult to put the same pressure on every key, so the resulting typing varied in intensity, as can be seen from the old letter below. Note also that all the characters occupied the same width, irrespective of whether they were narrow, like 'i' or wide like 'm' and that the letters appear slightly blurred because of the smudging of the typewriter ribbon.
Incidentally the letter shows the punctuation convention of the time, with more punctuation marks than became usual in later years. In particular, 'Mr' has a full stop after it. Being relatively short, the letter does not show the normal practice of the time of two or three spaces after a full stop. This practice was dropped when word processors became common.
Where a few copies were required, they were normally made at the time of typing not afterwards. This involved the use of carbon paper. Where more copies were required, there was the Banda and Gestetner.