![Using BookBub Ads to Drive Series Sell-Through [Case Study]](data:image/svg+xml;nitro-empty-id=MjU1Nzo5Mjk=-1;base64,PHN2ZyB2aWV3Qm94PSIwIDAgNzUwIDM5NCIgd2lkdGg9Ijc1MCIgaGVpZ2h0PSIzOTQiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyI+PC9zdmc+)
Promoting a deal on a first-in-series book is a great strategy for boosting sales of the entire series. Fantasy author Danny Knestaut took this approach to the next level: Through an efficient testing process, his BookBub Ads campaigns have helped bolster read-through across two series. By the time he and his coauthor were ready to launch a new book in their sequel series in December 2022, Danny’s process was reliable enough that he was able to exceed their sales goals — and he estimates they achieved a positive ROI and read-through rate. Here’s how he did it!
Campaign Goals
By promoting Dragon’s-Eye View, the first book in the Wisdom of Dragons series, Danny’s goal was to drive sales of The Wolf, the newly released third book in the sequel series, Dragonjacks. Danny chose to promote Dragon’s-Eye View because it’s the book where readers are first introduced to the two series’ main characters.
I hoped that if I moved a lot of copies of the series starter, read-through of the series would eventually lead to sales of the new book.
Danny planned to discount the book to free for five days, the KDP Select free period, knowing that free books can effectively hook new readers. To prepare for the free deal, Danny ran test ad campaigns in September 2022 for Dragon’s-Eye View at $0.99, discounted from the regular price of $2.99. What he learned from these tests helped set him up for a great campaign promoting the book for free in December and boosting sales of the related Dragonjacks series.
Phase 1: Testing Dragon’s-Eye View at $0.99
First, Danny went to Amazon to pull a list of authors from the also-bought books for Hordesmen, the final book in the Widsom of Dragons series. He wanted to know which authors were selling books to the readers who made it all the way to the end of the series.
My goal wasn’t necessarily to sell a lot of books, but rather, to find out which audiences would respond best. Audiences that performed well would get slight bumps in their budgets during the campaign so that I could be sure that the audiences were genuinely responding and that it wasn’t a fluke.
Danny targeted these audiences with small budgets of $5–$12 and high cost-per-click (CPC) bids above $1.
My strategy is to run week-long campaigns featuring price discounting. When I discount a book, I want it known far and wide, so when the BookBub Ads dashboard shows me the range that the average winning bid is bidding, I bid a few cents over the high end because I want to make sure that I’m winning most bid auctions. No one can buy my book unless one knows it’s for sale.
Danny also targeted the audiences of himself and his coauthor, Vickie Knestaut, aiming high with a CPM (cost-per-thousand-impressions) bid of $20.03. He chose an ad creative that proved successful in previous tests:
I subscribe to the BookBub newsletter, and the first thing I look at when it shows up in my inbox is the ad. I want to see what others are doing, and I pay attention to the ads that catch my attention and those that turn me off. I take inspiration from the other advertisers who are putting out ads that make me want to click. I then create a variety of ad creatives and test them to find the ones that get the highest click-through rate (CTR).
In this case, the tests generated very high CTRs — as high as 16.5%! Most importantly, Danny met his goal of learning which audiences would respond best. He was ready to apply this knowledge to driving sales of his new release.
Phase 2: Discounting Dragon’s-Eye View to free
For the free deal in December, Danny targeted the five top audiences from the September test campaigns, including the audiences of himself and his coauthor. For the ad creative, Danny created three different variations, all with the deal price prominently displayed to drive more clicks:
Considering it was for a limited time, I put that information in the creatives to help generate a sense of urgency, to let BookBub’s subscribers know that I was offering them a deal that would soon expire.
Danny tested all three image variations on his and his coauthor’s own audiences. He used just the left-hand image in ads targeting the audiences of the other four authors, this time using CPM bidding.
I use CPM bidding when I know I’m advertising to a tested, responsive audience because that usually gets me the cheapest clicks. If I’m not sure how responsive an audience will be, I use CPC so that I can find out without it costing a whole lot. Budget is usually determined by how much I can afford to spend, but when testing, once I know that something is not going to work, I kill its budget and shuffle the money over to the ads that are returning clicks.
Phase 3: Discounting book 1 in the sequel series
Danny’s next step was to drive follow-on sales of the sequel series, Dragonjacks. The day after the sale for Dragon’s-Eye View ended, Danny dropped the price of The Shepherd, the first book in the Dragonjacks series, to $0.99.
I then advertised it to just the audiences of myself and the coauthor. We had enlarged our audiences a good deal thanks to the success of the Dragon’s-Eye View promotion, so I wanted to hit our newest readers right away, while we were still top-of-mind, and let them know there was even more.
Each ad creative Danny tested featured the names of the two main characters, to let new readers know that the same characters were featured in this series as well:
Evaluating Campaign Success
Because Danny has been tracking the results of his BookBub Ads campaigns since he began using the platform in 2018, he has developed a general sense of what success looks like.
Over the years, I’ve learned what I can expect to see from various types of campaigns, so a successful campaign for me is one that did better than previous similar campaigns. Did I move more books? Did I move more page reads in KU? Did I have a lower CPC? Did I have a lower ACoS (Advertising Cost of Sales)? Did the sales rank peak higher during the promotion period? How many days passed before the second book in the series peaked below 100,000 in sales rank? All of this lets me know what a reasonable expectation is, and whether or not I exceeded it.
However, monitoring the ROI of campaigns for a free book can be tricky given that you don’t earn revenue from your downloads. To work around this, Danny looks at sell-through rates to other books to determine his returns, which he estimates based on the sales and Kindle Edition Normalized Page (KENP) reads from book two in the series.
When doing a free campaign, how many free books I give away is important, but the more important thing to me is how many sales/KENP reads did I get on the second book in the series. That’s where the money is at. Knowing how many people went on to the second book helps me gauge the read-through and then estimate how much money I am likely to make off the campaign. Although there are a handful of factors that go into whether I consider a campaign successful, sales and KENP reads of the second book are the most important metric to me.
Results
Dragon’s-Eye View got a total of 2,836 free downloads while the ads ran. This increased attention continued to generate paid unit sales and KENP reads of the book after the free deal ended, as well as increased sales and KENP reads of the second book in the series, Letting Go.
Danny estimated that the read-through rate from book 1 to book 2 after 30 days is approximately 2.15%. Usually, he’ll plug the sales and KENP reads into a spreadsheet that calculates revenue generation based on historical read-through data. In this case, Danny estimated — based on the activity of the 30 days following the start of the campaign alone — that he can expect to see approximately $900.32 in revenue if read-through rates remain at their historical averages. The entire campaign cost $587.09.
It was profitable. Also, I’ve sold more books, both free and full-price, than I had planned on, so my goals have been exceeded.
While it’s more difficult to calculate how many of the new Wisdom of Dragons series readers went on to read the Dragonjacks series, both The Shepherd and The Wolf also had sales increases after the ad campaigns.
Read-through across the series is still strong, and all seven of the books that feature the same main characters are currently my top seven bestsellers for the month.
Here are the results from one of the top Dragon’s-Eye View free campaigns:
Takeaways
The advice I would give that is specific to promoting a first-in-series book would be to look to the last book in the series for ideas on which audiences to target. The people who will read the last book in your series are the people you want to introduce your first book to.
As for how Danny plans to use advertising as part of his book marketing moving forward:
I plan to do more of the same. I test new ideas as I come across them, discard what doesn’t work, and double down on what does. Soon, I will be rebranding a series, as well as introducing a new one, and I look forward to using BookBub Ads to A/B test new book cover concepts before deciding on which covers to commit to.
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Click to tweet: Authors, promoting a deal on a first-in-series book is a great strategy for driving follow-on sales. Here’s how fantasy author Danny Knestaut does it — his advice and results from this recent campaign are awesome! #pubtip http://bit.ly/3ELLPJf
Click to tweet: “The advice I would give for promoting a first-in-series book would be to look to the last book in the series for ideas on which audiences to target.”
More brilliant ideas from Danny Knestaut in this case study on his advertising strategy: http://bit.ly/3ELLPJf #bookmarketing
