These little 3 x 3 notecards were cases from the Stampin Up leadership event this year. I also have made matching envelopes with my diagonal score board.
Here is a PDF file with all the measurements for different size cards.
And here is how I made the 3 1/4″ x 3 1/4″ envelope:
Cut a sheet of paper 5″ x 5″
Then score on the diagonal at 2 1/4″ on each side
Cut out the corner notches as shown
Corner round the four corners
ITEMS USED TO MAKE THESE CARDS:
Several people have asked how to make an A2 envelope that holds a 5 1/2″ x 4 1/4″ card. By folding an A2 envelope differently you can make a pocket envelope.
First cut your paper at 6 3/4″ x 10 3/4″
Then score 1/2″ on each side as shown below
Score at 3″ and at 7 1/2″ as show below
Cut the corners along the score lines as shown below
Corner round all corners if desired
One way you have a pocket envelope as shown
And folder the other way you have a standard A2 Envelope as shown