2) Scene setting
And do it quickly: Not too much description on the first page. Just enough. Place the hook, then get out for a bit, and come back.
The internet is littered with advice like this. This particular version came from a Facebook post by Jason V Brock (that's a link to his Wikipedia page).
Personally I think it's like all advice (on writing and everything else). Listen to all of it, take it seriously and then do what works for you.
With that in mind, here's the opening sentences to some recently completed stories:
They say the man from Suffolk seemed in fine fettle they day he died. ~ A Clowder of Cats
Dougal Brown ate dirt. ~ Digger
The Coachman’s Arms brought comfort and a wide range of beers and wines to its patrons.
~ The Codger
“I figure I have an hour, maybe less, and so for those of you who come in to find out what the hell happened. Excuse the chains, but this is it. An eyewitness report. ~ The Resolute Report
I have 123 photographs of my back. ~ The Tao Of The Tattoo
Richie returned to consciousness in a room that smelt like the high school locker room after a championship game. ~ Rite Of Passage
The Sharps rifle is the finest weapon ever invented by man, the .50 calibre shot can be fired by a competent marksman at a rate of up to ten rounds per minute with deadly accuracy. ~ Walking The Line
And for a bonus, the opening line of the yet to be finished Pisces of Fate, the sequel to Engines of Empathy
In the warm tropical waters of the Aardvark Archipelago swims a fish that no one likes.