fitcityblonde's Road Trip Guide to Hwy 1

First, you'll need a car. The 1 is littered with Jeep Wranglers, convertibles and sports cars if you're feeling fancy, but any car will do. Once you've got that covered, it's time to hit the road! Head South on Highway 1 from SF, and you'll reach each of these wonderful spots (sequentially) along the way:
Pacifica

It sounds crazy, but the critically-acclaimed "most-beautiful" Taco Bell is here. Get out and check out the surf!
+ Best Hike: Devil's Slide Trail
Half Moon Bay
Mavericks (a surfing location here) is world-famous for some of the largest waves in the world in the winter time, when the waves come. There's a great beach trail for walking and surf-viewing here. You can also go beach horseback riding.
Places to eat:
The Barn (American, beer garden) - cute little outdoor spot!
Half Moon Bay Brewing Company (seafood, brewery) - and there are a bunch of other cute places around it! My father and I recommend the flight (pictured above :)
Sam's Chowder House (seafood) - always looks packed, but it's a much-bigger space than you think. I'd love to sit outside sometime!
The Ritz-Carlton - you can order a s'mores kit and sit outside and watch the waves, while cooking marshmellows over an open fire pit.
+ Best Hike: Fitzgerald Marine Reserve
Pescadero
There's a cool lighthouse here (Pigeon Point Lighthouse) and they have elephant seal guided walks at Año Nuevo State Park.
Santa Cruz
The Beach Boardwalk has a bunch of amusement park rides... You can hop out and ride two roller coasters (the Giant Dipper and the Fireball) and grab a dipped ice cream cone and be on your way. West Cliff Drive is really pretty as well.
Monterey
Monterey Bay Aquarium is always fun! There's a boardwalk here too (Fisherman's Wharf), but it doesn't live up to the rest (though you could probably grab some decent fish and chips here). They also have dolphin and whale watching tours.
Pebble Beach
You can do the 17-mile drive starting near Monterey and cover Pebble Beach (and the lone cypress tree, golf course, etc) and wind up in Carmel.
+ Best Hike: Garrapata Bluff Trail
Big Sur

If you don't do anything else, go see McWay Falls (pictured above). Pfeiffer Beach is gorgeous and Bixby Bridge is an iconic must-see of Big Sur (you may have seen it in Big Little Lies?).
+ Best Hike: Pine Ridge Trail (20-mile roundtrip hike to the Sykes Hot Springs!).
Hearst Castle
I've never been, but have only heard good things: http://hearstcastle.org
San Luis Obispo
This is the furthest I'd go. There are some wineries here if you want to do some wine tasting (Tolosa seems popular).