This is an easy origami heart, great for rookies and pros :)
Since I officially suck at explaining, the pictures may help you more than my description of the step.
Also, since the bottom of the heart opens, you can also use it as a book mark.
Step 1: Step 1: paper
I used printer paper for the instructable, but origami paper or any other will do.
Cut it into two connected squares.
Step 2: Step 2: creases
Folding one square at a time, fold diagonally (so the creases form an X) and fold backwards to create a line that runs down the center of the X.
Step 3: Step 3: triangles
Follow the creases and press the two squares into two triangles.
Step 4: Step 4: find center of the triangles
Step 5: Step 5: fold flaps toward vertex of the triangle
Take each little flap and fold them toward the vertex of the matching triangle.
Step 6: Step 6
Open up the flaps and press them down to four squares.
Step 7: Step 7
Fold back one side (either side will do) of the bigger square.
Step 8: Step 8
Turn the origami over, and fold back the corners that are sticking out.
Step 9: Step 9: start the decoration
Fold the sides of each small square toward the center line (the diagonal).
Step 10: Step 10: almost done
Open up the new "pockets" (<- I really can't think of a better word for those little things....-_-...again, I suck at explaining. Sorry), and press them down.
Step 11: Step 11: finishing touches (extra help)
Fix anything that doesn't look quite right, and-------*DRUM ROLL PLEASE!* You're done!
Use it as a Valentine's card or rip it up to show your hatred toward love, or do whatever your heart desires :)
Also, I published a video on how to fold this on Youtube, check it out if you still need some help:http://www.youtube.com/watch?v=T2_RBxK6DVY