Advance care planning (ACP) has focused on documenting life-sustaining treatment preferences in advance directives (ADs). The ADs alone may be insufficient to prepare diverse patients and surrogates for complex medical decisions.To understand what steps best prepare patients and surrogates for decision making.We conducted 13 English/Spanish focus groups with participants from a Veterans Affairs and county hospital and the community. Seven groups included patients (n=38), aged ≥65 years, who reported making serious medical decisions. Six separate groups included surrogates (n=31), aged ≥18 years, who made decisions for others. Semistructured focus groups asked what activities best prepared the participants for decision making. Two investigators independently coded data and performed thematic content analysis. Disputes were resolved by consensus.The mean±SD patient age was 78±8 years, and 61% were nonwhite. The mean±SD surrogate age was 57±10 years, and 91% were nonwhite. Qualitative analysis identified four overarching themes about how to best prepare for decision making: 1) identify values based on past experiences and quality of life, 2) choose surrogates wisely and verify that they understand their role, 3) decide whether to grant leeway in surrogate decision making, and 4) inform other family and friends of one's wishes to prevent conflict.Beyond ADs, patients and surrogates recommend several additional steps to prepare for medical decision making including using past experiences to identify values, verifying that the surrogate understands their role, deciding whether to grant surrogates leeway, and informing other family and friends of one's wishes. Future ACP interventions should consider incorporating these additional ACP activities.