When writing a couples name, for example, in a Christmas card, is there a particular way round you should write their name, such as the male then the female?

I always think it depends on the recipient of the card. If it's someone that I know best, I put my name first. If the connection is through my husband, then his name goes first.

Are you referring to addressing a card envelope? Today, if the woman has kept her own surname, or if the two are unmarried but co-habitating, you should just put the names on separate lines: "Mr. John Smith", with "Ms. Jane Doe" written just below it. It actually doesn't matter which name comes first, but you should try to ascertain whether the lady likes "Ms." or prefers "Miss."

If the couple are married, the woman is using the man's surname, and you want to be very informal, you can address the card to "John and Jane Smith," though my mother would kill me if I did that.

No, actually inside the card. I'm asking because today I recieved a wedding invatation saying 'to Mike and Liz' inside, even though the people who sent us the invatation have known me longer, so I wondered if there was a specific way round to doing it.

Ah, on the interior envelope of a wedding invitation, you are simply supposed to write the name(s) as "Mr. and Mrs. Smith" or:

Mr. Smith
Ms. Jones

First names aren't appropriate on except on very informal invitations, which don't usually have interior envelopes anyway. Again, the order doesn't matter in any etiquette sense, but I, too, probably would write the name of the person I knew best first. (On the other hand, I wouldn't get bent out of shape if someone I knew well didn't put my name first, especially since my name is multisyllabic and my husband's isn't. I agree that "Bob and Margaret" sounds better.