How to design serial covers

How to design serial covers
It has often happened that an Indie Author buys a premade cover from my site and from this cover he wants to create a series of a defined number of books that usually start from 3 volumes upwards.
The first thing I ask is to inquire, before making the purchase, if it is possible to create a series for that cover. Usually the answer is yes, but it is always better to inquire first.
Serial covers are distinguished by several important factors. One of the first factors is the title text and the author’s name which must be the same, a trademark, for all covers. Branding is important in distinguishing the author’s footprint. One way to characterize the branding of a series is to keep the same design by changing only a few colors in the graphics. This is a cheaper and faster way of making a series. Another system that distinguishes the branding of a series is to keep the same color scheme, text and placement of graphics. it has also happened that several premade covers purchased from my site become a series. At that point it is sufficient to create a branding for the texts that will distinguish it in a collection.