Hold the cravat in front of you, as shown, with equal length ends.
Put the cravat across the front of your neck, crossing the ends in the back.
Bring the loose ends forward again, adjusting the fit so it’s comfortable but snug.
Cross the loose ends in front.
Make a simple knot, but leave the knot loose for the time being.
Make another knot in the opposite direction, again leaving the ends loose.
This is actually a close-up of the properly formed knot created in step 6.
Pull the loose ends tighter, but leave them a bit loose to leave some form to the knot. If you pull the ends too tight, the knot will be unattractively small.
If you like this look, adjust the tie against your collar and leave it untucked from your vest.
If you prefer a more tidy look, tuck both ends down into the vest.