If you'd like to diamond farm the way I do, I suggest having both diamond multipliers and the fly faster gamepass!
Okay, this will be different depending on whether you have gamepasses or not, but i do have all of the gamepasses, except the crystal ball, So here is mine:
I usually Get on to the New Royale High and hit the major diamond spots in a few minutes, I usually get 800-1000 diamonds in 2 minutes. then I get off the server and get on a new one ....then repeat, until I have the amount I want/need. (The diamond spots I go to: The top of the light house, behind the waterfall near the light house, in the cave behind that waterfall, In the cave behind the swimming pool waterfall, On a diving board, In a tower behind spawn point, In a tent behind/to the left of spawn, in the sewer pipe to the left of the front of the castle, In the Art room behind the glass {let me know if you need to know how to get behind the glass}) ~Have questions, please ask!~