How do you send money on animal crossing

Create a letter addressed to whoever you want to send money to. You can create a letter by buying stationary at Tom Nook's, selecting it in your inventory, and writing a letter. Once you have a recipient and a message, exit out of the letter writing screen, and you should have a letter that says "To -insert name of recipient here-" where your mail is. Get Bells from your Bell counter to your inventory, and then drag the Bell icon in your inventory onto the letter. If you see a present icon on the letter, you've done it well so far. After that, go to your Post Office, and mail your letter.