This is a bit different than most of the topics TPV addresses, but one of the tasks of a successful indie author is to promote the author’s books.
Newsletters and social media are likely the most common tools for these promotions (although PG would be happy to hear about others). However, standing out in an inbox or on an Instagram feed is not simple.
Images are one means of standing out. Colors are another.
From Shutterstock (All images are from Shutterstock with additional information about each image in the OP):
Looking to refresh your work with the most popular new color combos? Revamp your designs for the new year with these three on-trend neons.
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With influencers and tastemakers looking to neon as the next big color trend in fashion, it makes complete sense that analysis of the Shutterstock search data revealed these three energetic hues as the colors that Shutterstock users are most excited about right now.
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This flouro green takes natural influences and exaggerates them, throwing them into a digital sphere. Think The Matrix, Flubber, and the iridescent scales of geckos and chameleons, and you’re on the right track.
UFO Green strikes the perfect balance between nature and technology, making it the perfect color to bridge the gap. Use it to create designs that are at once peaceful and reviving, as well as forward-thinking.
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UFO Green is the younger, more fun-loving sister of nature-inspired greens like sage and forest. Enhance the natural tropical tendencies of UFO Green by enhancing your photos with flouro green filters.
Neon typography is an eye-catching way to evoke a nightlife mood, and works especially well on events flyers and posters. This neon font has a classic, vintage-inspired style that evokes Parisian absinthe bars.
Link to the rest at Shutterstock
PG understands that not all the ideas in the OP will suit a particular author’s taste, but climbing out of an appearance rut may improve visibility and engage readers and prospective readers better than only updating the written message in new promotions.