Regardless of the type of event you’re inviting your guests to, you should use a formal writing style on a formal invitation. This means spelling out dates and other words that are usually abbreviated.
For example, you should write “Saturday, the nineteenth of November” instead of “Saturday, November 19th.”
You should also write “253212 Boston Street” instead of “253212 Boston St.”
Write out guests' full names.
Don’t use the shortened versions of guests’ names.
Write “Stephanie Smith”
instead of “Steph Smith" and always use last names.
Include the hosts.
For example, you should start a dinner invitation by saying
"Sam and Ellen Smith invite you to a dinner celebrating the graduation of their daughter Leslie from graduate school."