Jesters' shoes are regularly brightly coloured, but also curl up at the toes.
An oft-documented side effect of the perfect male orgasm is that his toes curl upwards just prior to the money shot. Thus it resembles a pair of jesters' shoes, at least in shape. It's a phrase often used in the Fat Slags strip in Viz comic.
Hence, getting to the jester's shoes, having the jester's shoes, etc.
See also: vinegar stroke, rat stance, up and over like a pan of milk.
"And there I was just getting to the jester's shoes with Nathalie when in walks her father, who, as you know is built like a brick house privy..."
If your feet go multi-coloured during sex, however, you are advised to seek medical attention. This is not normal.
(Sources: Viz comic passim, personal experience.)
(5 of 30 of my IRON NODES. I was going to do something longer, but I've been judicially reviewing a certain London borough all day and I'm bushed. So sue me.)