I read summary and Book's last page , it must have a happy end

sometimes I read the back cover first and other times I see a movie and then I find out there is a book version of it and if I like the movie I look for the book at the library.

I don't even know! I get recommendations from friends, magazines (People actually tends to have good recs), Daily Show/Colbert Report, the library. I'm usually reading several at the same time :)

If I was browsing at a bookstore, I would judge a book by first it's spine, illustration cover and then blurb. Then I wipe out my phone and check the ratings and reviews (no spoilers) on goodreads to make a better decision.

A lot of the times, I get recommendations from friends and family. Once I have read a particular good author's work, I would go searching for their life work and see if they can be added to my 'to read' list :)

I recommend these two authors for their world building:
Brandon Sanderson - Mistborn trilogy
Anne bishop - Black Jewels trilogy

Happy reading!

Genre, then title (particularly if it's funny or somewhat preposterous), synopsis, then finally flip to the middle of the book and start reading at the top of the page, no matter where it is in the paragraph. If it's compelling when the author isn't expecting to have to grab a reader's interest (like on the first page), it's worth reading.

This works particularly well for old pulp science fiction and fantasy. Their titles are outrageous.

I'm a lot like you, Stroctoperry. Genre comes first for me, then the back blurb. Title I normally discount, because titles can be awful but aren't always the author's fault. Then I read a little from a few random inside pages.
After that I usually set the book down, look at other stuff, and then come back and stare at it five or six more times before finally deciding to buy it (assuming it looks good).
I'm very wary about buying books blindly, though, so I normally go off of recommendations.

Genre first, then the cover, then the summary and then I look at reviews. Usually on goodreads. I haven't been to an actual bookstore in years.

I look at the cover then read the summery. If I like it, I'll read the first chapter.