If you want to do the tour alone, i.e. without an agency/guide, you should register/de-register with the police and mountain rescue service. Previous acclimatization and experience in high-altitude mountaineering are mandatory. You often need a 4x4 vehicle to get there (depending on the time of year). Even though it is hot in San Pedro de Atacama, it is cold up here. So take appropriate wind and heat protection with you. At least 2.5 liters of water and don't forget sun protection! Any uncovered area of skin burns within minutes! Technically simple, trekking poles are helpful, but be sure to take crampons with you if there is snow and ice. Then have fun and always take it slowly! 🤙