There really is only one Version for this card shape but I am going to show the finished card first, Inside and Out as you need to get the concept of how the card works before seeing the instructions.
Once you get the concept the card is very easy to make.
1. This is the front of the card closed and therefore the Outside of it.
2. When you start to open the card up this is what you begin to see.
and though it is actually the inside of the card as it flips over it becomes the outside and stands up in a tent shape.
Now you have the basic concept
3. Onto the instructions. You will start with a piece of cardstock (do not use a thick card. 160gsm is about as thick as you want. Cut to 9.5" x 5.5". Score across the 9.5" edge at 4.25, 4.75" and 5.25"
3.Fold card in half (as if making a conventional card)on the 4.75" score line. You can also see the score line that you made at 5.25".
4. With card facing you as picture above fold the card stock back on itself at the 5.25" score line. Card should now look like below.
5. Turn cardstock over and you will now see the one remaining score line. Fold the right hand edge of card over to the left hand edge and crease on the score line.
6 Cardstock should now look like below.
and when laid out flat should have a v shape vent along the middle of card as below.
7 Open card back out and run double sided tape down either side of the centre fold. (In the grooves).
8 Remove tape and stick together as below.
This now forms the inside of the card base.
9 Decorate as required. The right hand side will be the front of the folded card and the left the back.
Here I have die cut two strips of butterflies and attached them either side of the ridge. which makes thee tent fold shape.
10 The front of the card still looks like this so decorate as required.
I have created a note for the front so that the recipient knows there is a hidden surprise inside.