Cathedral of Light: Complete the Cathedral of Light capstone dungeon to unlock higher World Tiers.
Fallen Temple: Follow up by clearing the Fallen Temple capstone dungeon.
Farm Normal Dungeons
World Tier 4: Set the difficulty to World Tier 4 and farm normal dungeons until you reach level 50. Your friend will handle the combat while you gain XP by being present in the dungeon.
Farming Gold
Sell Unneeded Gear
Dismantling Gear: Sell spare armor and weapons to vendors instead of dismantling them. This will provide a steady stream of Gold.
Use Greed Shrines
Location: Greed Shrines can be found randomly in the world or within dungeons. These shrines boost Gold drops significantly for a limited time. Seek them out to maximize Gold earnings during their active period.
If you have any specific questions or need details about something in the game, feel free to ask(mmoexp).