I tried to weld but it doesnt work. When I start the game the ears just pop off and fall. Please help I dont know how to weld properly.
you always have the option of using a weld plugin: https://www.roblox.com/library/148570182/Weld-Plugin in this one just use ctrl + click to select two parts. Or you could use a script like this: https://www.roblox.com/library/181259635/qPerfectionWeld-Perfect-welding-for-EVERY-situat although the script would need to be changed depending on your intentions.
--Edit-- Use this article it should help a bit! https://developer.roblox.com/en-us/api-reference/function/Humanoid/AddAccessory