The best way to boost your sales rank is to sell books!
There are other ways too. Some involve cheating though, and this is likely to cost you in the long run.
However, there are other ways of potentially boosting your sales rank without BAD-about-it.
Read on, if you want to get a quick Espresso boost for your very best creations!
1. Manuscript Improvements (Best Version EVAAAAHHHHHH!)
When was the last time you did a proper, thorough edit of your ebooks?
Or when did you last notice a typo and thought ‘Nah, [insert-edgy-satirist’s-expletive-of-your-choice] it?’
It is sometimes possible to boost your traffic merely by updating the manuscript, although I am not sure how universal this is.
As with other suggestions here, this is just meant as a goad to provoke you into doing your own more detailed research.
Again, don’t B/A/D about it. I would speculate some vendors, or other companies like Pronoun, Smashwords and Draft-2-Digital might penalize you for deliberately manipulating your stats by overdoing this; similar to other suggestions here. It’s really not advisable, and it would not surprise me if it cost you a sales rank penalty in the long run, or some other sanction.
I don’t know if anyone has a specific policy on this (officiailly announced or otherwise), but I strongly advise you not to be clever about this.
So, if you actually do need to make some corrections, that is obviously fine.
But cynically and artificially manipulating your sales ranking (e.g. by changing your book several times in a month by omitting chapters or poems or stupid stuff like that) is not good.
Anyway, your readers will be able to see any updates you make; if someone decides to download your latest update, they will not be happy to see you are messing about. This will harm your reputation in the long run.
So for a great many reasons, it is not OK to use this measure, or any other measure, in a dishonest way. I’m trying to show you ways of legitimately boosting your sales rank in a way that benefits you, your readers, and the vendors; I’m sure you yourself are OK, but there’s always one!
2. Update Your Metadata (I): It’s All About The Blurb (Or Not?)
Is your blurb too short, or too long?
Too longwinded, even?
Or even too badly proofread?
Does it give too much away, or too little?
Ideally, you want to tantalize the reader and reel them in; but without making them feel they already know already.
Obviously, keep any massive spoilers or ‘twists’ to yourself. Self-control is best.
Do you know anyone who has written a blurb for a successful book?
Or have you seen a good discussion online about how to do it?
3. Update Your Metadata (II): Keywords and Labels
Pronoun allow you to find useful statistical data for keywords.
Of course, not all of you are using Pronoun.
No matter how you publish your indie books, you can still have a good think about how to use keywords effectively.
Popular keywords have more people searching for them; but you are faced with some stiff competition from other books with similar keywords.
Less popular keywords have fewer people searching for them, but it’s not as competitive in relation to other books by other authors.
Keep an eye on what’s trending too! For example, if there is big news in Turkey or Mexico or the Philippines or Australia, you might be able to capitalize on this.
Distinguish also between long-term and short-term themes.
For example, a minor local political scandal might not last very long. But other themes like war, or terrorism, might be longer term trends; but there will likely be peaks and troughs there too.
Similar principles apply to categories too.