Literature

Usually word of mouth - but that can be either from people I know (friends, fellow online people), or sometimes it might be buzz from the media. Usually that's in the form of CBC's Canada Reads. I don't often pick things up based on retailer suggestions.

When I see a book mentioned enough times in contexts generally aligning with my tastes (also depends on how much I trust the context: an ad will have near-zero impact, a direct recommendation from a close friend will have high impact, for a review it depends), I decide to give it a try.

As for your situation, you'd benefit from having a reviewer with good taste and solid reputation. It might be quite a challenge, but it's probably worth it once you've made sure your book doesn't suffer from trivial flaws. Or, if it's just a hobby, you might choose not to bother, or to have more practice first.

Word of mouth, NPR interviews/segments, or if I flip through it and I vibe with what little I can skim. Also if it's non fiction and especially historical non fiction about something I'm interested in I'll def read it.

A good portion of my library is hand me downs from my in-laws. Luckily they are really cool people and have good taste.

Mostly word of mouth and reading online reviews. r/suggestmeabook and r/weirdlit were great resources for me as well.

Since I primarily read via the library, I'm not really worried about "wasting money" on books I wind up not liking, so I can be more adventurous with reading new authors I'm not sure about.

Short-stories is how I discover new authors right now. Either through a collection or free on the web.

Having the book available through an early reviewers program (that's how I've discovered a couple of author I didn't know of), having the book on sale (there are many sites which pick on books that are on sale) or promoting the book through social media (TikTok seems to be very popular right now).

I pretty much exclusively do the WRONG thing and judge a book by its cover.