Taking care of business and making friends may sound unrelated at best, but here's a secret: the dreaded term "networking" is basically just jargon for making friends.
Writing is a lonely business. You pull out your laptop, put on your headphones, and enter into a world that you created and no one else knows about (yet: one day they'll be writing FanFiction in your world). If you're lucky enough to be writing full time (and don't all of us, somewhere, have that goal in the back of our mind?), that's pretty much all you do.
Write stuff: no human interaction required.
There are, of course, a few issues with that. For one thing, how do you write Deep Truth About The Human Condition if you aren't around other people? For another, writing is lonely. I know I'm repeating myself, but it's true. You write alone, you face writer's block alone, you revise alone, you read rejection emails alone.
Here's the thing: you don't have to. Making friends might be one of the key ways to keeping your sanity during the long and crazy process of writing and subsequently selling a novel. There are Twitter hashtags to follow (#amwriting is common; right now, #CampNaNoWriMo is a big one. And there's also #amrevising and #amquerying for other stages of the writing process); word sprints to join; and friends to be made.
If Twitter isn't your thing, writers love to blog. Search people out. Interact with writers on their blogs and through their Twitters, their newsletters, their Facebook groups... I do all these things, and I've made a lot of friends through the Query Tracker forum, too.
Besides keeping you sane and making friends from around the world (which should be all the motivation you need), making friends really is networking (which is a very scary word. Sorry about that.). Other writerly friends make great critique partners, ones who are willing to tell you, "You can do better than this. Don't take the easy way out." And you'll listen, and they'll read the revision, and they'll let you know they love it. You'll know they're sincere since they weren't afraid to tell you when they didn't love it.
When you get an agent, you'll want people to tell who understand what it means to actually have an agent. (I don't know about you, but this basically discounts my real-life family and friends.) When you go on submission, it's great to have friends who can send you pictures of cuddly animals to keep you sane and remind you that this, too, shall pass. And when you get the book deal you've always wanted? It's time to celebrate, and celebrations are always better with friends.
Twitter is full of now-published authors who have been friends since the days of querying. The most famous for their friendship is probably Susan Dennard and Sarah Maas, both now published successfully. And because they're writing BFFs, they get to blurb each other's books, and happily promote each other on Twitter, and collaborate on projects.
A quick reminder: Never treat someone like they're just a business deal waiting to happen, or befriend someone only because you think they'll help your career. It won't work. That's why I call it making friends, and not networking.
Befriend someone because you both have an undying passion for knee socks, obsess over Lizzie McGuire even though it's been off the air for 11years, and neither of you are sure what the big deal is about coffee. Oh, and you happen to both be writers. Maybe one of you rocks at dialogue and the other is excellent at filling plot holes. You'll make a great team, the two of you, with two books that both have killer dialogue, no plot holes, and obscure references to fancy knee socks.