On Writing Romance by Leigh Michaels
1. Do not start with a flashback or include one in the first chapter. Flashbacks are confusing when the readers haven't yet established a connection with the characters and the story.
2. Do not start with a dream or with a character waking up. A dream sequence is usually confusing and hard to explain. Starting with a character waking up is almost always a variation on starting too soon. Instead, begin with the character's first important action.
3. Do not start with a long, descriptive passage. Beginning with a sentence or two of description to provide context is often useful, but readers want to get acquainted with the characters, and they're usually interested in the background and the scenery only as it affects the characters.