San Pedro de Atacama is the usual base. Tours leave daily for Laguna Chaxa, Laguna Cejar, Tebinquinche, Toconao, Socaire, and the altiplano lagoons. Self-driving is possible on some routes, but distances, unpaved roads, and changing access rules make local advice valuable.
Carry more water than you think you need and do not rely on mobile signal away from the main roads. If you are combining the Salar with higher lagoons, acclimatise in San Pedro first.