Here's a headstart on Valentine's Day - a postable 3D Valentine sliceform. The components easily slot together and fold flat. It fits into a C6 envelope. Tag and charm included.
Here's your free print-and-cut Valentine heart:
Print the template on 160gsm photocopier card. (The finished model will look nicer if you pick up a colour from the design and print the flip side of the card with it first. Or, you could glue all the the side pieces in back-to-back pairs so they are double-sided.) Cut out the pieces, taking extra care with the slots. Glue the big heart back-to-back.
To assemble the sliceform, slot the side pieces without Love X on either side, facing outwards. Next, slot in the Love X pieces. Downward slots and upward slots interlock.
Enjoy making your simplified sliceform heart! :D