Maybe these pictures will help
This is at step 21
Step 21, from the behind
The beginnings of the fold. Basically, just fold the point backward. You can see that the top of the point is sort of unfolding. There is only one way this fold can actually happen, that is why there are no guide folds for it. Just start folding, and it will happen.
That same portion is now pretty much completely unfolded
The fold is almost complete
Done. Step 22 just has mountain folds.
I didn't want to repeat the steps on the back flap, so I just made a little stand for the heart and roughed out the wings.
I hope that helps! If you've got any more questions, feel free to ask.