I've often heard that the first three pages of a story are the most important. This is true and I've often started those three pages again and again until I felt they were right. While reading a Writer's Handbook that's almost 30 years old I came across an essay by Shelly Lowenkoff. I don't know the writer but her advice put in the things I try to put in those important three pages. So Just what are they.
Start with an important action rather than starting with a list of a character's movements. What I've heard is to start in the middle of the action, a moment before the action starts of a moment after the action has occurred. This will bring tension into the story and also raise questions in the reader, like - what is going on, will the character manage to escape what every is going on.. This point will stir the reader's curiosity and make them want to read on. While starting near the action, you will put the characters under stress and this can lead into giving a clue as to their desires and their motivations. You do not need to spell these out in the opening pages, hints and clues are enough to let the reader know there is some kind of conflict to come. Conflict is what makes a story vivid.
You need to let the reader know there will be more than one character so a bit of foreshadowing can be a plus. Not much and this will depend on the type of story you are writing. If a romance, the heroine or hero needs just a thought that they're looking for romance. A mystery will have the main character thinking about the villain and so forth.
The first few pages will also establish through whose eyes the story will be told. There may be more than one character who has a viewpoint but putting both in the first three pages will make your opening a bit muddy. Decide who has the most to lose or the most to win and put the opening scene in their viewpoint.
Three pages isn't much but you need to establish setting and the area where the story will be played out. The area is a bit different than the setting. Setting is places. Area is background like sports, medicine - the area where the characters will play out their drama.
If you can establish these elements in those important three pages you'll find they bring the reader to comtinue turning pages because they want to know what will happen to these people next.