I fancied a go, as some good friends of ours got married last year. I got to be a bridesmaid and Big E was a groomsmen.
Ages ago I'd seen a lovely idea to use the score of the couple's first dance as a backdrop to the card. Our friends' first dance was "Your Song" by Elton John. I searched on Google and found the sheet music! Now...the website seemed legitimate and open access, but I am sorry Elton John if I have downloaded your copy righted material!
Their wedding colour scheme was green.
Step 1: Choose your colours and song sheet. It was easy to fiddle with the print size of the song, so I could make it the right size.
Step 2: Stick the layers together. I just used a standard glue stick.
Step 3: Cut out a little heart shape. I then decorated it with gold pen with their names, but you could just put the date or whatever you fancy.
Step 4: I left it at this stage for ages, but as I was putting in it an envelope, I added their wedding date to the top.
I hope they like it. :)