I know it’s difficult to really see what the rider in the above picture is wearing, but it’s hard to find a photo or picture that shows what the actual Pony Express uniform looked like.
Pony Express riders were given uniforms to wear. The uniform consisted of blue pants, a red shirt, gloves, and a pair of boots. However, most riders found the uniform uncomfortable and instead, chose to wear buckskins.
Riders also carried a rifle and a pistol. One website I visited also said they carried a bugle they would blow, when approaching a station, to alert the stock tender to have a fresh horse ready when they rode in.
However, the majority of my research says the riders let out a “coyote yell” when approaching a station to alert the stock tender to have a fresh horse ready. A “coyote yell” is a noise they would make with their mouth and didn’t need an exterior instrument to create.