My advice: start with something out of the ordinary: an unusual image, (“Miss Melody liked to knit jackets for trees”) a question (“why is Jonathan lying on the road in the middle of the night?”) or something which gives you an emotion (“when my cat went missing, I would have sold my soul to the devil to find her”.)
OK, you got the reader's interest. (I just made those sentences up off the top of my head.) Now you can expand a bit on them. As a reader I might want a quick checklist to get myself oriented: time? place? (is it in the USA? Planet Jupiter? Persian empire, 2000 BC?) Who's the protag? (readers are like disembodied parasites. We need to find a head to jump inside, before we can be taken around on a tour and see, hear, smell and feel things.)
But don't hit readers with over-description. Writers are advised to "show don't tell". Well, I think that advice has to be taken with a grain of salt. Sometimes it is better to just tell something quickly and move on. Do you like to walk into a new person's house and be bombarded with their life story? I don't. On page one, I don't need to be bombarded with information about what kind of car Joe drives, the name of Miss melody's dress designer, the business partners in CrapCor, Inc. There's lots of other things not to start with, like the name of the King of the Blarghh empire and the geneology of his wizard and what the Ancient Scrolls say, or a detailed schematic of the Starship Smersh and it's Trilithium Phaser system.
Also, please don't hit me over the head with a violent death scene. Who wants to open a book, only to have 10 ninjas come after them and chop off limbs with magic swords that spit dragon fire? You get the idea. It's a bit over the top. (Well, maybe some people like it. The ones who play video games all day. I guess you need to know your audience.)