Correct way to mail a letter?

Well first you should start by addressing the letter correctly... For USPS mail should be addressed something like this:

Mr. John Smith

124 Main ST

Anytown OH 01234

It is best to include a return address incase you forgot postage or you mailed it to the wrong address.

Next you want to use a USA First Class Stamp. These can be purchased at the Post Office Window or places such as Mailboxes Etc., The UPS Store, Publix, Kroger, etc.

You then want to place your letter in either a residential mailbox or a vestibule at the local Post Office.

Good Luck! :)