The Portofino peninsula's 60km of narrow trails are a world away from the sinuous sports-car-lined road from Santa Margherita. Many of them are absolutely remote and all of them free of charge. The tourist office has maps.
A good but tough day hike (there are super-exposed sections) is the 18km coastal route from Camogli to Santa Margherita via San Fruttuoso and Portofino. There are handy train connections at both ends.