As young adults transition into adulthood they must develop effective self-regulation techniques to help them navigate the heightened expectations of independence placed upon them. During this challenging developmental stage, mentors and other supportive individuals can facilitate co-regulation processes that help young adults reach self-regulation. This qualitative research identifies and characterizes supportive processes of regulation that graduate student mentors engaged in as part of their mentorship interactions with undergraduate mentees with learning disabilities and attention-deficit hyperactivity disorder (LD/ADHD). Participants were part of a larger campus-based study with 52 undergraduate mentees with LD/ADHD and 57 graduate student mentors. Data were transcripts from mentor group meetings (N = 20) discussing LD/ADHD and the mentorship experiences, undergraduate group meetings (N = 13) discussing LD/ADHD experiences and supports, and an instrumental mentor case study. Structural coding was used to identify content related to mentorship experiences; process coding was used to describe the actions and roles undertaken by mentors; content analysis was used to examine relative salience of topics discussed during mentor group meetings. Four themes emerged describing the ways in which mentors acted as co-regulators for mentees including: Fostering Positive Relationships, Guidance Based on a Similar Path, Supporting Strategy Generation, and Supporting Mentees by Setting Limits. Findings highlight key actions and processes for effective co-regulation techniques used by disability-informed mentors, that support the self-regulation practices of undergraduate students with LD/ADHD to reach their educational, career, and personal goals.