Many sites provide information on dayhikes in Big Sur - see below for links to some such (non-commercial) websites.  Here I provide selected dayhikes I've found most enjoyable, with emphasis on having something interesting, a "Claim to Fame", setting them apart from other dayhikes.  These hikes are not particularly short, often being a day's adventure. 

When planning a hike consider the season.  Fall is a great time for river hikes, or anywhere that requires driving on a dirt road, since creek crossings are easy and dirt roads driveable. In winter and spring, consider ridge trails after a storm the creeks will rise.  Summer is the least desirable season - hot, with flies, and fewer water sources.  More Big-Sur-specific hiking basics.

For hike difficulty, note both total mileage and total elevation gain - in Big Sur the latter is often more important, with many ups and down along a route.  And of course the trail conditions - brush definitely increases hike difficulty!  For these hikes, expect reasonable hiking conditions, especially for State Park trails - but for non-state-park trails it's best to check the latest trail conditions, which also shows any closures.