Other than ensuring the oak leaves are free from fungal infections, nothing much. Just collect them up, put in black binliners, make sure they're nice and damp by watering if necessary, stick a few holes in the bottom of the bag, tie the top and stand somewhere out of the way for at least a year, probably 2, till they've become dark, crumbly soil. Process can be hastened by running a mower over the leaves to chop them up a bit before bagging.
In my experience, all the leaves I've done this with take 18 months to 2 years, regardless of variety.