Park in the National Trust car park at Godrevy (the one furthest from the road; the first two you come to are for the beach)
Then just follow the coast round to Navax Point and back. Look out for the dragon sleeping in the cliffs as you walk back to the car park.
Virginia Woolf's novel "To The Lighthouse" was based on Godrevy Lighthouse which shone for the first time on 1st March 1859. It is now solar powered and fully automated.