This is a very simple pattern, all the ones I found were hard to understand and always went wrong at the heel, so I decided to make my own and add some photo’s for clarity.

To make bigger or smaller you can either add less or more decreases to the toe area remembering to also increase the heel size (the first row needs to be just over half the stitches)
You could also go up or down hook sizes and yarn weight although this would give less size difference.