If you're going to lie about a career, I would recommend choosing a career that you're actually interested in. Because, eventually, and especially in a small town, you're going to come across someone who is interested in that field, and they're going to know a thing or two about it. You can say you're "new", but they'll still expect you to know the bare minimum. If you're interested in it, say as I hobby, it's easier to remember the research you do, and you look more excited about it when you talk about it, which makes it more believable.

You could also do whatever it is you're lying about doing. For example, one person mentioned writing. You could actually write a story/blog/poem. No one ever said it'd have to be good enough to be published. But then, when people ask about it, you have physical evidence. And it's easier to remember the details and keep the story consistent when you have established a thorough story. Not to mention you don't have guilt getting in the way, or fear of being caught, because ... technically ... you're telling the truth.

Of course, this is a lot easier when it's something you're actually interested in, because then it seems less like a chore. It doesn't have to be writing, you could do self-help blogs (then say you prefer to stay anonymous online in case of potential stalkers). Or writing recipes for cooking, if you enjoy that. Then, when asked for recipes, not only will giving them recipes validate your lie, you'll be appreciated for it.