Gender and sex diversity exist in humans, but are often seen as too complex for scientists to incorporate beyond a female/male binary or placement on single dimensions. Here, we demonstrate a novel method for assessing and visualizing diverse gender/sexes using diagrams adapted from sexual configurations theory (SCT; van Anders, 2015). We asked participants (N = 242) with diverse gender/sex identities to locate their genders, sexes, and gender/sexes (i.e., “gender/sex configurations”) by marking and writing on SCT’s diagrams via an online platform. Results showed that visualizing gender/sex (a) demonstrated the complexity underlying seemingly simple gender/sexes such as “woman” and “man,” and (b) provided a way to systematically describe seemingly complex gender/sexes. These findings suggest that SCT visualizations provide a way for people of diverse gender/sex identities and experiences to represent the fullness and complexity of their gender/sexes in ways that can help create a more inclusive psychological science. This article is Part 1 of a 2-part report, and Part 2 explores the ways participants reacted to and perceived SCT and this novel survey (Beischel, Schudson, & van Anders, 2021). (PsycInfo Database Record (c) 2021 APA, all rights reserved)