The year is optional on invitations, but it must be used on announcements.
If the wedding is in a place of worship, then the phrase, “the honour of your presence” is used. If the wedding will take place at a home, or in a hotel or elsewhere, then phrases such as, “the pleasure of your company” or “the honor of your presence” is used. This has to do with the sanctity of holding a wedding in a sacred place.
If the city is large and the wedding site is not well known to your guests, then the address should be printed on the invitations.
With well known cities such as Washington DC, San Francisco and Atlanta for example, it is not necessary to list the state. However, for layout and spacing purposes you may prefer to do so.
The party after a wedding is called a reception if it takes place after one o’clock. It’s called a breakfast if it takes place earlier than one o’clock.
The time for the ceremony typically is written “at four o’clock” or “at half after four o’clock.” The abbreviation A.M. and P.M. are too informal and never used, but a couple may substitute “in the evening” or “in the afternoon” or “in the morning” if they wish.
No nicknames and no initials. Full names should be used unless one you hates your middle name so much that you just can’t bear to have it known.
If the word junior is used, it is written lowercase, unless it is abbreviated. Then it’s capitalized – go figure, I can’t explain this one!