The document provides a step-by-step guide to using the 3'aQTLatlas database, which contains an atlas of approximately 0.4 million genetic variants associated with alternative polyadenylation (APA) identified across 15,253 RNA-seq samples from 49 human tissues. The guide describes how to use the database to search for and view 3'UTR APA quantitative trait loci (3'aQTLs) across tissues, compare 3'aQTLs to genome-wide association studies, and search for disease-associated 3'aQTLs in specific tissues.