I would totally recommend using Zygor's if you are leveling alts or don't care about the quests you're doing, because it offers a huge leveling advantage in terms of streamlining what you do. Just let the arrow tell you what to do and you never have to think about where you're going or what you're doing. When I use this addon (and the leveling guides) I definitely understand why he charges for it.
Gold for riding training. Travel time is a SIGNIFICANT time sink while using quests to level. You don't want to wait to get it. In fact, while questing, the second you ding 40/60/70/80 you'll want to hearth and train it IMMEDIATELY! 10304 gold is the base cost, which will be modified by reputation. Also, make sure you're in a guild with the 10% riding speed bonus unless you're a class that already gets a mount-speed buff.
":" - Any time a step ends in a ":" instead of a "." means that the next step is part of the current step you are on. This generally means the next step should be done while working on the current step. This means every "start working on" or "continue working on" will end in a ":". But this is used with other occasions as well, so keep this in mind.
You can earn a decent amount of XP by doing Herbalism or mining. Any zone works but I prefer Sholazar Basin as a lot of the mobs are not aggressive and the mobs are spread out so you will find a lot of herbs and ore that you don’t have to fight for. It is possible to make about a level every hour by doing this, or a level every 30-40 minutes with rest XP.
There are other in-game guides out there such as Xcelerated, but it doesn’t even come close to what Dugi and Zygor offer. Although I’m obviously a fan of Dugi Guides, I have given a fair side by side comparison of each guide, based on facts and what is offered by each. I’ve included many screenshots to give you an idea of how each guide looks and works within the game. I will do my best to keep this as up to date as possible, with price changes, guide updates etc as I know how annoying it is reading outdated reviews.
But compare that with BfA's lackluster prepatch. Last week, players' uber-powerful Artifact weapons, which they had spent the entire Legion expansion building up, abruptly burnt out with no in-game explanation, no storyline, no quest, no Dad jokes from Khadgar, just a line of text on the Artifact screen saying they had been sacrificed to help stop the destruction of the world--part of the ending quests for Legion.
Tiragarde Sound and Stormsong Valley are both fairly similar zones, but Stormsong is a little longer, meaning that you might not even have to finish it to hit 120. Tiragarde also comes with a bit of a warning. There are plenty of side quests to do in the zone after you finish the story quests. Don’t do them. It’s not worth the time or the experience you’ll get.