Stretching routines can be adjusted for flexibility by varying the types and durations of stretches. Incorporating both dynamic stretching (before activity) and static stretching (after activity) can enhance flexibility progressively. Focusing on areas that are frequently tight, such as hips, hamstrings, and shoulders, is beneficial. Additionally, holding stretches for longer durations, typically between 15-30 seconds, can improve muscle length over time. Consistency is key; adjustments should accommodate individual needs and fitness levels for optimal results.