An assistant store manager functions as support for the manager in charge. This support can look different, depending on what industry you're working in, but generally you'll assist with daily operations.
The daily operations may require you to supervise employees or it may require you to solve an issue with a customer. Whatever role you pick up that day, you'll want to make sure you're carrying out the goals of the manager and owner.
Generally, you'll only need a high school diploma to become an assistant store manager although, some employers may require that you earn a college degree. As an assistant store manager, prepare yourself for work beyond 40 hours each week.