One way is to begin with a description of a lonely place, like 'In the desolate cemetery, the cold wind blew through the withered grass as the old tombstones stood in solemn silence.'
You can also start with a sad event from the past that still haunts the character. 'Every time she passed by that old oak tree, memories of that fateful day flooded back. The day her world had turned upside down and nothing had been the same since.' This immediately creates a melancholic mood as it shows that the character is still affected by a past tragedy, and the reader wants to find out what exactly that event was.
One great way is to start with a vivid description. For example, 'The sun was a blazing ball of fire in the sky, casting long, menacing shadows across the desolate landscape.' This immediately sets the scene and draws the reader in.
Starting with the loss of a loved one can be very effective. You could write, 'She was sitting alone in the empty house, the silence echoing the absence of her mother who had passed away just a week ago. Every corner of the house held memories of her, and now those memories were all that was left.' This immediately sets a sad tone as the main character is dealing with a great loss.
One way is to start with a vivid description. For example, 'The sun was a blazing ball of fire, searing the parched earth as the lone traveler trudged along the dusty road.' This immediately sets the scene and draws the reader in. Another way is with a thought - provoking question like 'Have you ever wondered what it would be like to be invisible?' It makes the reader curious and eager to find out more. A third way could be starting with an interesting dialogue. '“I can't believe you did that!” she exclaimed, her eyes wide with shock.' This creates intrigue about what happened.
One way is to begin with a mysterious setting. For example, describe a dark and enchanted forest where strange noises come from the thick bushes and an otherworldly mist hovers. This immediately sets a fantastical mood.
A good way to start a mystery story is to introduce a strange event. For example, 'The old clock in the attic started chiming at midnight, even though it hadn't worked in years.' This immediately creates a sense of mystery and makes the reader wonder what's going on.
Begin with a strange sound. You could write, 'In the dead of night, a low, grating moan echoed through the forest. It was a sound that sent shivers down the spine of anyone who heard it, yet no one could tell where it came from.' This immediately creates a sense of mystery and fear.