Step 1:
Prefold over these 4 lines. Then, turn the paper.

Step 6:
Press the 2 layers indicated by the smaller arrows against each other. Then press the loose piece flat from above with your other hand, see large arrow.

Step 5:
Pull the piece indicated by the arrow upwards by making a valley-fold over the yellow line.

Step 2:
Make a valley-fold over these 4 lines.

Step 4:
Make these folds from the edge of the model to the center, not any further. First, make 2 valley-folds below, on the right. Then, make 2 mountain-folds in the middle. And make 2 valley-folds on the top left.

Step 3:
Turn the model.

Step 10:
Press the edges indicated by the arrows flat from above.

Step 8:
Unfold the folds from step 7

Step 9:
Pull the edge indicated by the arrow upwards by making a valley-fold over the yellow line.

Step 7:
Make a valley-fold over these 2 lines.

Step 16:
Now the model is closed again. Repeat step 13 to 15 on the other 3 triangular pieces.

Step 15:
Press the 2 petals towards each other again, in the direction of the arrows.

Step 12:
Repeat step 6 to 11 on the other 3 loose pieces, see arrows.

Step 11:
Fold the triangular piece above the yellow line downwards by making a valley-fold over this line.

Step 14:
Fold the triangular piece above the yellow line to the inside of the model by making a mountain-fold over this line.

Step 13:
Pull the 2 petals at the bottom of each arrow outwards, in the direction of these arrows.

Step 21:
Turn the model.

Step 19:
Make a valley-fold over these lines, all lines are prefolded.

Step 20:
Now you've made an extra petal. Fold this petal upwards by making a valley-fold over the yellow line. Repeat steps 17 to 20 on two other same pieces of the model. (you don't have to do anything with the 4th same piece)

Step 18:
Pull the upper layer of paper loose from the rest of the model at the places indicated by the 2 arrows.

Step 17:
Push the 2 pieces indicated by the arrows towards each other by making a valley-fold over the yellow line.

Step 22:
Fold the piece on the right of the yellow line to the left by making a valley-fold over this line (=bookfold)

Step 28:
And repeat step 24 on the other 2 petals, see arrows.

Step 25:
Press the petal a little further downwards, in the direction of the arrow.

Step 26:
Repeat step 24 and 25 on the other 2 petals with more paper-layers.

Step 24:
Fold the petal indicated by the arrow downwards by making a valley-fold over the line below and a mountain-fold over the upper line. (The line below is already prefolded).  Make the same folds on the other side of the petal. Make sure this is a petal with more paper-layers.

Step 23:
The model has 7 petals now: 4 petals are made of more layers then the other 3. Fold this petal downwards by making a valley-fold over the yellow line. Make sure this is a petal with more paper-layers. Now the model has 6 petals that stand upwards. The 3 petals which are made of the least paper layers will be on the inside of the flower.

Step 29:
Make a mountain-fold on the tip of this petal (with less paper-layers), see short yellow line.

Step 27:
The 3 petals that still stand upwards are made of the least layers of paper. Repeat step 24 on this petal (not step 25!)

Step 30:
And make a mountain-fold over this short line. Make sure the end of this petal stands outwards, not downwards, when you make this fold.

Step 31:
Repeat step 29 and 30 on the other 2 petals with less paper layers, see arrows.

Step 32:
Make an inside reverse fold over the 3 short yellow lines on the right, see large arrow. Do this by making a valley-fold over the longer line in the middle and a mountain-fold over the 2 shorter lines. Make the same folds on the 2 other outer petals, see smaller arrows on the left.

Done!