In response to the global energy crisis and environmental challenges, this chapter emphasizes the critical role of flexible electronics in mitigating resource scarcity and e-pollution. Further, in-depth discussion on fabrication strategies for flexible electronic materials and devices, including material selection, structural design, and manufacturing processes, is provided. Metals, carbon-based materials, polymers, and composites with excellent electrical and mechanical properties are ideal for wearable health monitoring. Clever structural designs, including one-dimensional fibers, two-dimensional serpentine structures, and three-dimensional origami-inspired forms, greatly enhance the flexibility and adaptability of the sensors, ensuring that they provide accurate signal feedback when fitting the contours of the human body. In addition, this chapter explores the prospects of flexible electronics applications such as electronic skin (e-skin), flexible solar cells, and the integration of flexible display technologies with wearable sensors, providing innovative solutions for medical diagnostics, soft robotics, and future smart systems. Despite challenges such as mechanical robustness, multiple signal decoupling, signal stability, and environmental issues, innovative strategies are driving the field forward, boding well for a future of versatile and sustainable wearable electronics.