Wedding invitations set the tone for a wedding, and that tone should be elegance -- even if the wedding is downright casual. Although wedding invitations vary widely in style and design, one thing that etiquette experts agree on is that the outer and inner envelopes should both be hand-addressed. You don't have to do this yourself, however, and you probably shouldn't if your handwriting is poor.
By Hand, or the Next Best Thing
Even if your wedding is on the small side, writing each invitation by hand can be difficult and tiring. Calligraphy is the preferred style, but it's tricky to do correctly. For this reason, some couples hire a professional calligrapher. This can be expensive, however, so budget-minded couples often turn to computer programs that print calligraphic script directly onto the envelope. This is becoming more and more acceptable, although it's still not acceptable to use ordinary printed labels.
Outer and Inner Envelopes
Formal titles, including professional titles, should be used on the outer envelope, such as "Judge Vanessa Smith and Mr. Smith," although this style does not apply for the inner envelope -- just names. Here, for example, you can just write "Vanessa and John Smith." The first and last names of the guests, their children's names if invited, and the words "and Guest" for singles should be written on the inner envelope.