Write every day even if all you can manage is just ten minutes. Write what you want to write and not what everyone else thinks you should write. Your writing will shine when you've written with a passion, not with a dutiful attitude.
Read good literature, by that I mean the classics. The classics are full of substance and themes that transcend time, unlike most fluffy fiction today. Study the classics, the writing techniques used. You will emulate in your writing the literature you surround yourself with.