Adjusting your cleats

There are 2 simple goals with cleats:

Align the angle so your feet are in a natural position as you pedal. Your stance on the bike should mimic what feels right at leisure : if your toes point straight ahead, or in or out as you walk and stand casually, they should do the same as when you pedal. Take note of both feet: some of us end up pedalling with each foot aligned differently.
Align the fore-and-aft position so the widest part of your foot is over the pedal axle. If you have trouble dialing this in, put your shoes on, feel for the ball of your foot and mark it with your vertical line from a marker. Set your cleats so the line bisects the axle.

Unless you’ve had a professional fitting that recommends a deviation from the norm, your position on the bike should be as close to neutral as possible. Here’s the consensus on what a neutral position looks like :

When you’re seated, the angle of your knee should be between 25 – 35 degrees when the pedal is at its lowest point. Or try this very accurate ballpark; with your shoes off, your heel should just brush the pedal at its lowest point.
With your hands on the handlebar and brake hoods, the handlebar should obscur the front hub, or be just slightly in front of it, when you look straight down.
With the pedals horizontal, a string dropped from your bony joint just below your kneecap (patella, if you wish) should bisect the pedal axle.
With your hands on the handlebar and brake hoods and your elbows slightly bent, the angle formed by your arms and torso should be about 90 degrees.
With your hands on the bars,there should be about a 1cm gap between your knees and elbows at their closest position.
If you’re pigeon toed ……. : angle your cleat towards the outside of your shoe.
If you’re bowlegged……… : angle your cleat towards the inside of your shoes.