Open Stardew Valley
Go to the main menu
Select your save file
Click or tap the co-op option if you want to share a multiplayer invite code
Choose Host New Farm or Host Existing Farm
Start the game
Open the pause menu
Go to the Options or Multiplayer menu
Find the invite code or invite friends option
Copy the code shown on screen
Send the code to the person you want to invite
Make sure they enter the code in their game’s join or invite section
If using mods or a platform invite system, share the mod or platform invite code from the same menu
Keep the game open while others join