Choosing your first dog is a big decision. Get this right, and you’ll have the best friend for life. Get it wrong, and you’ll both be miserable. The good news: there’s a learning curve for everyone.

I’ve had dogs ever since I was a young child, growing up on a ranch with Great Pyrenees, Komondors and Anatolian Shepherds, which protected our goats from coyotes — and followed me as I ran around our ...