San Blas town is small enough to walk. The main plaza, the market, the canal embarcadero where boats leave for La Tovara, and most restaurants are within ten minutes of each other on foot.
For the beaches and surf breaks at Matanchen Bay, 10 km south, you need transport. Local colectivo taxis run along the main road toward Las Islitas; a private taxi to Matanchen costs a few dollars. Bicycle rentals are available from a couple of places in town and are a practical option for the flat road south.
Boat tours to La Tovara depart from the embarcadero near the bridge at the edge of town. Boatmen work from the dock and approach is easy — just show up. Longer birding or fishing boat trips can be arranged through local guides; the tourist office on the main plaza can help with contacts.