Any dinner party can also be an occasion to celebrate a birthday by adding a few little extras throughout the evening. Start by letting the guests know whose birthday you are celebrating when you invite them, then follow-up with the details.

Seating:  Make your guest of honor accessible to the greatest number of guests by seating him or her as close to the center of the table as possible.  Not only does this maximize the fun for your guest of honor, it makes every seat at your table desirable by being close to one of the hosts or the guest of honor.

Technically, the guest of honor is seated to the right of the host and their dinner partner is seated to the right of the co-host, however I prefer our less formal and more fun arrangement..

Decorations:  Add some decorations for the cocktail hour and dining area.  For the cocktail hour, hang a “Happy Birthday” banner along the front of the bar, on a wall, or across the front door. 

In the dining area, hang swirls or colored streamers related to your theme to add a celebratory feel to the dinner. Stick "Happy Birthday" gel letters on a prominent window or mirror.

PartySwizzle.com offers a number of birthday dinner party theme decorations.

Cards & gifts:  Dinner parties are perfect for birthdays because you can use the time between courses for birthday festivities. Plan to have the birthday boy or girl open cards and gifts between courses, right before the main course. 

This gives you a little extra time to get the main course served, and it is completely adjustable to you.  If you are ready to serve, let the birthday boy or girl open the rest of the cards and gifts after the main course and before dessert.

Cake & candles:  The dessert course is naturally the moment for cake and candles.  Don’t feel obligated to serve a traditional cake, any type of dessert will work just fine.  Plan a "Happy Birthday" musical accompaniment to play while serving the birthday dessert.