Front spoiler
The next part of the car we will model is the Front spoiler. This is a
very complex object and will take some time to create. First duplicate
the Hood. Then make the original Hood WF-invisible. Make sure you are in
Face Edit mode. Select the object called 'Copy of Hood' and rename that to
'Front spoiler'. Now, select all
faces of the Front spoiler, except these at the front rim, like shown in the next image:

All faces of the duplicated Hood object deleted, except these at the
front rim
Take a top view and go to Edge Edit mode and select the upper edges
to create new faces, just like you did before. Creating new faces from the
upper edges makes sure the spoiler also has a vertical edge, which you need.
Keep creating new faces, switch views when needed and use point editing to
match the blueprint.

The red arrow indicates how the shape of the spoiler should develop

new faces match the blue print (side view)
When the Front spoiler has the shape like shown in the last image, take a
front view. We need to add some extra edges to the object. The Front spoiler
contains large air holes, which we need to cut out from the spoiler. Because
we use an instance object, we only need to model one
☺
Modeling this is easy if you have edges at the same position as the air hole
has in the blueprint. So, when in front view, go to Face Edit mode and use
the Knife tool to cut some new edges to match the blueprint. Be aware that
there are two knife tools available! You need the one in the tool control
bar, which is shown in the next small image:

The knife tool you need... Edges added, to match the
blueprint
The next part is a little bit tricky. The cuts you made basically divides the
object in faces that will be used for modeling the air hole; the others will
be used for the front spoiler. Next images show how to proceed. The edges
which are marked red, are extruded downwards, just like you always did. The
blue edges you need to extrude inward. They shape the inside part of the air
hole. When modeling the air hole you will notice that you need to weld two
open ends together. Don't worry about that, we will fix that later on.

Edges marked red are extruded down, the blue edges are extruded inwards
Now continue modeling the mesh in Edge Edit mode and finish the shape of the
front spoiler. The areas around the Head light and the Mudguard are first
roughly modeled. We will fine tune the shape later in Point Edit mode.

In edge edit mode continue modeling along the lines of the blueprint

The front spoiler almost done now!
When the Front spoiler has the shape, similar to this image shown above, it
is time to do some fine tuning. The fine tuning process is best
performed in Point Edit mode. Let's start with the point where the wheel
area (Mudguard) and the Front spoiler come together. The points of both objects
(Mudguard and Front spoiler) need to be in the same position. Later we will
move the points of the Front spoiler a little down, to create a seam.
To accomplish this, we have a neat trick up on our sleeves. Perform the
following steps (read carefully!). Set both the Front spoiler object and the
Mudguard object in Point Edit mode. Then in the Select window select only
the Front spoiler and select all points that you wish to align with the
Mudguard.

Select a row of points that need to be moved
Then press and hold the Shift key, go to the Select window to add
the Mudguard object to your selection. This makes points of the Mudguard
object selectable (because it is in Point Edit mode). In the Transformation
tab select the Move tool and drag a small box around the fixed point of the
Front spoiler and then drag a small box around the target point on the
Mudguard.

First drag a box here..
Then one here...

and snap! the two points join at the target point!
This moves the two drag-selected points to the same position.
Repeat this for all points where you see fit.
The easiest way to move a single mesh point is to 'click and drag'. You can
also select a point and then use the Move command from the Transformation
tab (short key: m ).
Make sure all points match the blueprint and are aligned with the other
parts of the car. Then you can move all points at the top of the Front
spoiler to create a small seam.
Now it is time to finish the Front spoiler object. As
mentioned earlier, the air hole is not yet a closed object and we need to close the
gap.

We need to close the gap...
Go to Point Edit mode and select two opposite points, like shown in the next
image:

Two opposite points selected..
and apply the Merge tool..
Use the Merge command from the tool control bar. This merges the two
selected points together to a single point. To close the entire gap you need
to keep selecting two opposite points and merge them. If you select all
points and then apply the Merge command, you end up with a big mess, because
all selected points become one!
Next we need to set the Edge sharpness for several parts of the Front
spoiler. So here we go! Have a look at the next image. Select all these
edges and set Edge Sharpness to 'Semi Sharp' in the Property window:

Set these edges to Semi Sharp
Select the following edges and set these to 'Sharp' in the Property
window:

Set these edges to Sharp!
When you take a look at the reference
image, you can see that the glass of the headlights slightly cuts into the Front
spoiler. This problem is solved just like we did with the Mudguard. Copy
the Front spoiler object and rename it to 'Front spoiler Glass'. Go into
Face Edit mode, select the corresponding faces (that do not make up
the glass part of the headlight in the Front spoiler) and delete these
faces. The result is just a few faces that shape the glass part, which
cuts into the front spoiler.

The selected faces need to be merged with the Headlight Glass object
These faces form a separate object, which actually should be a part of the
Headlight Glass object. So, we will merge both objects. Select both objects
(Headlight Glass object first!) in the hierarchy and select the Merge
Objects (Merge O) button to make them one single object.

Objects selected...
Merge Objects button...
Hierarchy after Merge Objects
This concludes the Front spoiler part. This is a good time to save your work!