I know you've heard it before: the comparison of the need to practice with athletes or musicians and writers. If you want to remain competitive, or even competent, you, as a writer, need to practice. That's not the issue here. We know it's true.
The thoughts I want to give about writing practice are more practical. What constitutes writing practice? Do you need to run though rote exercises like musicians practicing their scales? Not at all! Writing practice can be whatever you make of it.
If your idea of writing is fictional prose, why not use your writing practice time on poetry? You might never let anyone see what you create, but it may spark story ideas, character traits, interesting settings, or any number of things to help your fiction. Or why not take ten minutes and whip up a flash fiction story? It may not be salable after that one pass, but that doesn't mean that you can't take time later to revise it into shape. Or not. Maybe you'll simply be happy with having created it, and no one needs to see it. That's the beauty of writing practice; it only exists to help you grow as a writer.
If you're not sure what you want to do in your practice session, why not choose a writing prompt? Bookstores, both brick and mortar and the online versions, sell plenty of books that have a number of writing prompts in them. Magazines like Writer's Digest also usually have at least one prompt per issue, and their on-line content usually contains a number more. Or hit your favorite search engine and type in "writing prompts," and you'll have plenty of options to keep your practice schedule fresh for years to come.
One thing to remember about writing practice is that it should be fun. Everyday you write isn't going to be a picnic. Some days the words fight you and refuse to get down on your page. It doesn't matter whether you're a novelist, a poet, a journalist, a screenwriter, or whatever; if you write, you'll have tough days. So why not rekindle your love affair with the written word by taking ten or fifteen minutes a day to enjoy yourself? If you do this, your writing will do nothing but prosper. And to me, that's what writing practice is all about.
Until next time, keep reading and/or writing!