Nail spicules and secondary ingrown nails represent a frequently encountered clinical consequence of improper free edge management during professional manicure and pedicure procedures. This study examines the biomechanical and procedural factors that predispose nail plates to spicule formation and secondary onychocryptosis, with the aim of establishing evidence-based principles for atraumatic free edge management. The methodology integrates a systematic review of peer-reviewed dermatological literature published between 2020 and 2026, clinical case analysis, and the author's proprietary Non-Invasive Nail Guidance System (NINGS), developed over more than ten years of licensed cosmetology practice. Results demonstrate that preservation of lateral nail plate margins and avoidance of corner excision at the free edge substantially reduce the mechanical load on periungual tissue, lowering spicule formation risk. The NINGS protocol incorporates five structured procedural steps and provides a standardized framework adaptable to professional nail education programs. Findings will be of interest to licensed nail technicians, cosmetology educators, dermatologists, and podiatry professionals seeking preventive approaches to common nail pathologies.