One of the most common mistakes new writers make is dumping blocks of unnecessary back story into the first chapter. If not, weave it into the story later. One of my methods is to set chapter one aside and look at chapter two, or chapter three and ask a few what ifs. If you have a choice of revealing character conflict through internal monologue or dialogue, consider using dialogue. Make sure the dialogue doesn't include too much idle conversation.
Unnecessary dialogue slows the pace.
Make each character's dialogue distinctive so the reader knows exactly who's speaking without the tags. Check to see if both your hero and heroine are in the last scene of your contest pages. Keep in mind that the reader judge will look more closely at the chapters than the synopsis. However, if you get to the finals, it's the synopsis that will carry you to a win. Editors are interested in the whole story.