Cut out two hearts from card, ours measure 30cm x 30cm. I made a template from paper to do this, folding it in half to make sure it was symmetrical. Cut a 15cm x 3cm rectangle in the centre of one heart and a door in the other.
Cut strips from the leftover card approx 7cm wide.
Glue gun or tape the strips onto the heart with a door creating the back of a box.
I then attached a small piece of ribbon as a handle for the door...
...and threaded a longer piece of ribbon through the top for hanging.
Glue or tape the post box front heart to the box.
Cut strips of coloured paper (A4 pieces folded and cut into 4 vertical strips are the ideal width), and create fringes by making multiple cuts along them.
Glue or tape the strips of fringed paper to the heart, starting at the bottom and working your way up the front first, then the back.
Finally work your way up each side from the bottom meeting and finishing at the top in the centre of the heart.