Be patient: vanilla WoW is heavier, especially when it comes to leveling / problems. Gold is hard to get, careers are slow (for example, it takes longer to mine nodes), and you need to be at least level 40 to reach the top.
Do not purchase ah equipment until needed. In the classic World of Warcraft, mounts are expensive and gold is not as easy to get as it is today. You will want to get 60% installation speed as soon as possible, rather than a new improvement in armor quality.
Be a good person. Without LFG and LFR, you will need to rely more on your reputation and guild to enter the dungeon and raid. There are even tasks that absolutely need to be grouped to eliminate the random elite mob.
Don’t worry about having top armor at every level. Heirloom will no longer exist and missions will not provide armor as they do now. Green / Blue / Purple drops are more rare than they are today.
Learn about instance portals. Without LFR / LFG, you will not be able to transfer to the dungeon immediately. You will have to go there and use the call stone to raise others. Also, when you die in an instance (if not), you will have to know how to return to the portal to restore life.
Upgrade your party major at party time and wait to maximize your craft major. Upgrade them when you get cushions, but don’t waste gold and time maximizing your forging skills at each new level. Once you are at a higher level, resources will be easier to collect and better able to extract gold and materials from global / instance. In addition, you need the gold of the mount.
Always make sure your ammunition / reagents are available. Long range weapons need to be supplemented with ammunition. Some spells require reagents. The last thing you want is in the middle of Westfall, there are no arrows in the quiver.
Choosing a course you like is not necessarily the best course you think. If you are bored during grinding from 1 to 60, you may feel exhausted and like yourself.
Try the talent tree. Unlike modern wow, trees in classic will be easier to mix and match. You will be able to really customize your role. But keep in mind that there is no double specification, and re specification costs a lot of money. Therefore, it is important to be careful and minimize the possibility of reassignment so that you can move into the desired structure at a higher level without worrying about too much gold.