Level with a pet if you can because it will help keep you safe. If your pet is tanking all of the damage from the enemies you’re fighting, you won’t have to. The other reason is that pets are easier and cheaper to heal than you are. If you don’t have a pet, make sure you know how to use your defensive abilities. You can’t level quickly if you are dying all the time.
As late as possible. Early on, you’ll want to follow the missions in Battle for Azeroth right up until you get the option to send a follower on a two-hour long quest. As soon as you get there, stop doing the War Campaign missions. You can come back to them once you have reached something like 119 and a half and finish leveling with those if you want. If you don’t use these missions to cap off your leveling journey, then they’re the first thing you’ll want to do once you reach max level.
Playing through these zones, each with their own unique but interconnected stories and refreshing designs, immediately brought me back to how I felt when I played vanilla World of Warcraft and some of its earliest expansions. Instead of being a hero with near god-like powers like in recent years, players are back to being more grounded adventurers (going on more grounded, but still enticing adventures).
Im pretty much Herb Alch for life because I like not having to rely on anyone else for my consumables. The addition of Sky Golem completely changed herbalism for me. All professions are represented with the 11 warfront quest and I can promise you if you know how to play the AH a little you can make a fortune off the items required for turn in. That also being said, profs were not a big focal point for me on my months of beta testing. I went herb alch on the first pre-made character just so I could have consumables for Raid and M+ testing.
Congratulations on reaching Level 120! There are a myriad of new things to do. The first thing you should do is head to your faction hub ship where you have been doing your mission table quests and footholds to pick up and complete the quests necessary to unlock World Quests. World Quests will provide you an opportunity to grind reputation levels, acquire gear, and gather Azerite. There are tons of new things to do that we will cover in our Level 120 Battle Guide found here: Level 120 Battle Guide