You will have to drive to Punta Lobos in Todos Santos for this hike. See below and use your phone for gps directions.
The trail starts behind the old turtle processing plant. Right before you get to Punta Lobos look on your left for an old stone building with no roof. Go through the building and the trail will be off to your left.
You can either hike to the old port or continue on the trail which will eventually bring you to Las Palmas Beach. Las Palmas will take you about 2 hours for a one way trek. I would recommend dropping off a car at Las Palmas and only go one way if you decide to take this route. If you want a smaller hike just go to the Old Port and come back the same way you went in. This should take you about 45 minutes each way. It’s best to go on a low tide and you can swim there depending on the swell. I would not recommend swimming if there are big waves.
There is also a Sea Lion colony you can view on this hike. Once you get to the top of the mountain and the trail turns to the left to go down the hill to the old port you will see a small trail on your right. You can take that trail to the cliffs to view the Sea Lions. Be careful going this route, the cliffs are really big and there is a lot of exposure in some spots.