In my opinion, Zygor makes the best WoW leveling guides. They have been around for more than 10 years, which shows their commitment to maintaining and updating their guides to provide you with an optimized leveling path for any class and race, whether it’s Horde or Alliance. Zygor is an addon that includes a waypoint arrow and a separate window with instructions that, taken together, show you step-by-step how to level your character to 120, FAST. You’ll know exactly what to do at all times. It’s also very easy to jump in at any level; you don’t have to start exactly at level 1 or 110 or anything. It’s a bit more expensive than the other options, but I’d say it’s definitely worth it.
Edit 20 It’s been a week since this post and a lot of people are still reaching out to me with questions which is fine. I have had a few different people reach out to me to help make YouTube videos based off this guide and more info in BFA which I’m more than willing to do. Whoever gets the videos up first I will link them here for you guys to enjoy.