How should I wear the Amazfit GTS 3 for accurate health measurements?

Wear the watch strap neither too tight nor too loose, leaving enough space for the skin to breathe. When measuring blood oxygen saturation, avoid wearing the watch on the wrist joint, keep your arm flat, maintain a comfortable and appropriately tight fit, and keep your arm still throughout the measurement. External factors such as arm sag, arm sway, arm hair, or tattoos may cause inaccurate results or measurement failure. (Page 8)