The color guard is a non-musical section that provides additional visual aspects to the performance. The marching band and color guard performance generally takes place on a football field. The color guard performs alongside the marching band. The purpose of the color guard is to interpret the music that the marching band is playing via the synchronized work of flags, sabres, rifles, the air blade, and through dance. 

There are many different types of spins and tosses that can be done with the flag. Each spin or toss creates a different illusion and can be used for different tempos. Basic color guard moves include Jazz runs (a Jazz dance move used as a graceful way to run across the marching band field or the gym floor), "right shoulder" (positioning the flag with the bottom of the pole by your belly button and your right hand by the flag's silk tape) and "stripping the flag" (holding the flag silk with your fingers so you won't reveal the color(s) of the flag.) Flags frequently have weights -generally 1 in. carriage bolts or the like- in the bottom and top of the pole to make it easier to toss the flag into the air. However, even with the weights, weather conditions such as wind and rain can affect a flag's spin and disrupt a toss if not correctly considered.

From: https://en.m.wikipedia.org/wiki/Color_guard_(flag_spinning)