Emacs has a built-in help for BIBTeX so that you don't need to memorize or know all of this formatting. To use the Emacs help, simply save a blank document as .bib and then use the additional help buttons like "Entry Type" to have Emacs automatically create the syntax for the required and optional fields.
Please note that you will need to do minor editing if you use the automatic entry fields in Emacs for BIBTeX because Emacs is super helpful and slightly changes fields, like having ALTauthor instead of author. The ALT part can complicate things, so be sure to take that out before running everything and being frustrated by a detail like this.