There is no single right way to open your novel. There are many. Still, hooking readers with a line strong enough to drag them through hundreds of pages of dialogue and description is a daunting task, and a few guidelines can help you conjure the right words in record time.
Make Something Happen
The best opening lines in most thrillers and mysteries feature action. Something happens immediately, and the rollercoaster starts at the top of the hill. This may be literal action, like someone throwing themselves from a car, drawing a gun, or waking up to a mysterious creak in their bedroom. The action may be implied, or the audience may see evidence of something horrible, like a dead body on the floor, a smear of blood on the wall, or the quiet implication that someone is stalking a target.
Less violent novels often open with action, too. Someone may announce they are breaking up, starting over, etc. Dialogue is a perfectly valid opening, after all, and it forces opening scenes to move quickly while still providing a lot of critical information.
Open a Mystery
Why do we keep reading stories? Because we want to know what happens! Opening with a sentence that creates a mystery, creates a question, or just leaves readers asking “Why?” is one of the most reliable hook techniques in the business.
Even better, this technique can be combined with essentially any other. If you start with an action, leave the motives unclear. If someone jumps out of a moving car, don’t tell readers why. Make them question your character’s motives for a good page or two before revealing anything. You may wait several chapters before showing your hand.
Showcase Your Voice
Your individual voice makes your entire project unique, and it can/should appear in your first sentence. This may mean a biting one-liner introduces your protagonist, or you eloquently describe your setting while introducing your main character – see The Hobbit for one of the quaintest but surprisingly effective introductions in history. Essentially, be yourself, and utilize your voice from the very first sentence.
Scary things, first pages. First sentences evoke even more fear, and clever writers must always remember: they can change everything later. Anxiety kills creativity. It locks up your muse in a steel cage and starves it while you sweat and stare at the cursor. To beat that fear, keep in mind that writing is more an exercise in fluidity than anything else. Things change a million times before you give up and declare it “Good enough.” That includes your first sentence. Just as you’ll have several drafts of your novel before you’re finished, you should have several drafts of your opening sentence. Brainstorm at least five and play with each of them on the page. Which works best as a hook? Which introduces your first scene well? Can you combine elements? Maybe the first page needs to shift to accommodate the opening sentence.
It’s up to you, and it’s all going to change. Write a line of action, hide your motives, and say it as only you can. Then get on with the rest of your book, because a great appetizer better lead to a fantastic meal.