How to level from 30 to 40 in WoW Classic? Basic Guide

Here is a guide on how to level from 30 to 40 in World of Warcraft Classic:

1. Once you reach level 30, you will have access to new zones where you can continue leveling up. The next zones will depend on your faction, but for Alliance players it could be Arathi Highlands, Alterac Mountains, or Stranglethorn Vale and for Horde players it could be Desolace, Stonetalon Mountains, or Dustwallow Marsh.
2. Take on all the quests available in the new zones. These can be found by talking to NPCs (non-player characters) with a yellow exclamation point above their heads. Quests will provide you with experience points, gold, and items that will help you level up.
3. Kill monsters while completing the quests. Killing monsters will also provide you with experience points. Be sure to pay attention to your character's experience bar, and to group with other players to kill monsters more efficiently.
4. Complete dungeons like the Scarlet Monastery & Razorfen Down. You can access these dungeons by talking to the NPC who starts the quest chain which leads to the dungeon. Running these dungeons will give you a lot of experience and will also give you a chance to get some good gear.
5. Repeat steps 2-4 until you reach level 40.
6. Once you reach level 40, you will have access to new zones where you can continue leveling up. The next zones will depend on your faction, but for Alliance players it could be Tanaris, Hinterlands, Feralas or Badlands and for Horde players it could be Feralas, Tanaris, Badlands
7. Keep in mind that as you progress and level up, you will encounter tougher monsters, and it will take more experience points to level up. But as you level up, you will also become stronger and able to take on more challenging content.
8. Also, you can use the map to check for available quests and where to find them, and use the quest log to track your progress and turn in completed quests.
9. Finally, it is important to keep in mind that leveling up in World of Warcraft Classic can take a lot of time, so be patient and enjoy the journey.

Finally, don't hesitate to join a guild, they can help you with leveling, and offer you the chance to make new friends, and also they can help you with group quests or dungeons.

Also remember that as you level up, you should visit the trainers in the main cities to learn new abilities and skills, and also visit the vendors to buy new gear that will help you to be more efficient while leveling. And don't forget to use the rested XP system, this will give you a bonus XP when you are logged out or AFK in an inn or capital city.