First of all, you should consider the book cover size. Choosing the right size will make your book to look pleasant and proportional. In this case, you will have to create a cover that is 68cm large than the height of the chosen book size and 36cm wider than the width of the selected book size. It is also essential to note that there is a variation of 36cm in then trimming and folding process. By doing this, you will be in a position to come up with the book cover size that complements the design.
Apart from that, you should also think like a reader. It is essential to note that cover images and texts must be clearly understood as thumbnails which are how most of the books are sold today. You should know that a cover needs to make the reader feel something than telling them something. Therefore, how you feel when you look at your book cover is the same way your readers are going to feel.
Besides, you should also think of the cover as a critical piece of the puzzle. One thing that you should know is that writing a book is being compared to solving a thousand puzzles. Therefore, after writing it, you will have to find the right design that will attract the attention of your targeted audience. Make sure that you research the different book writing platforms so that you can see how different authors design their book covers. This will give you a better idea of how your book cover should be.
Also, you should also nail your audience. Where you will have to think about your audience which is essential in giving you a better idea of how your book cover should be. In this case, you will have to talk to your friends or the people around your area so that you can get their ideas on some of the things that they like. This will help you in coming up with a book cover that they will definitely like. Click here for more info.
Last but not least, it is essential that you stick to your key message and write it down. In this case, you will have to write down what the point of your book is and then you have that sentence in front of you to act as a reminder and a guide. Don't be mixed up in a situation where you have different designs, and you don't know the right one to go for. Learn more here: https://www.britannica.com/topic/book-publication.