Hand signals must be in accordance with the International Regulations for Preventing Collisions at Sea. In the rest of hand signals must be in accordance with content, you can find all the resources we have researched on this subject and examine them in detail.
Learn basic hand signals you can use while hiking or backpacking, including "stop," "go," "wait," "help," and more.
Site:
https://www.rei.com/learn/expert-advice/hiking-hand-signals.html
Order Hand Signals are visual cues used to convey instructions to drivers, aircraft marshals, and other ground personnel.
Site:
https://www.oes.psu.edu/facultystaff/freet/pdf/O15-1502r.pdf