You can be a reader without being a writer, but you can’t be a writer without being a reader.
Nothing beats the tags “he said,” “she said.” Anything else can distract from the dialogue, especially adverbs (http://www.dictionary.com/browse/adverb?s=t).
You need never say “he shrugged his shoulders” or “she nodded her head.” “He shrugged” or “she nodded” is sufficient.
The first-person point-of-view is limiting; the third-person point-of-view is limitless.
If you tell your story from too many different points-of-view, you run the risk of readers being more interested in one person’s story than another’s.
Words, to the writer, are like colors to the artist; diction is knowing how to mix them.
Don’t just write what you know, but also what you love.
It’s okay if your novel has the preexisting condition of being terrible. Your insurance is in the editing.
Write every day, even if it’s nothing more than a couplet. (My minimum is 300 words.) Freewriting counts. The water cannot flow until the faucet is turned on.
If you have too many flashbacks, you may have started your story in the wrong place.
Your characters had lives before you chose to write about them, but never feel you must “catch the reader up.” The reader cares about the present, & the past, only insofar as it affects the present.
If you have a family, you have a gift that keeps on giving.