Adult Birthday Invitations theme should be selected very carefully depending upon the nature of the party. If it is completely informal in nature where close friends and relatives are going to be invited then choose casual colorful theme and when office colleagues and seniors are to be invited the theme needs to be a bit serious with special emphasis on color combination. You can also see 50+ Birthday Party Invitations here . The body of the Birthday Invitation should start with very cordial greetings, then 2-3 lines regarding the purpose of the invitation and end it with your name, venue, date and time of the party. The invitations will look fabulous if you can add a smiling face of yours on the right hand corner of the invitations. These are available in supported file formats like word, pdf, and psd etc.