You must use photo reference, at least at first, or you will get stuck,
our brains use some extra processing for faces.

You can’t just copy a face on a canvas,
because you are not seeing the person correctly.

Similar thing happens with the moon when it grows large,
the moon never comes closer to earth, it is always the same size...

Our brain is just doing extra processing,
or not processing things at the horizon correctly, if you like.

The difference between looking into distance,
and looking afraid.

Can be as little,
as showing a thin white line beneath the iris.

You won’t be able to see that,
not very easily.

You do not want to play,
find all the differences in the two images during your painting.

You may not even be able to find,
that it is that bit of white beneath the iris that’s changing he entire expression.

Or that the lower eyelid must be rosier,
and area beneath the eye needs blue...

Or, you are going to hit the uncanny valley hard,
you do not want the brain to say "This human is not real" - or worse, yikes.

There are people out there who draw freehand,
some dare try to paint live subjects.

And that is a kind of a trick,
they relay on the fact that nobody will tell the artist: “This does not look like me.”

So it is like being hypnotized in front of an audience,
during a live show.

Everybody, ends up pretending they got hypnotized,
if hypnosis was actually real...

All the cops in the world,
would be trying to hypnotize their perps to get them to talk.

“Sir, I need you to put your hands behind your back,
and look deeply into my purdy eyes.”

The folks who draw fantasy art,
just letting faces come together as they practice their skills with reference in hand...

Are not painting real people,
all that often.

Some do it, and holly molly it is extraordinary,
when it works.

Today they are the little known leaders of modern art,
history will certainly remember them.

So you can’t just look at a breathtaking stylized painting,
and feel discouraged that it would take you four days to do it.

The artist might have been training on a pretty image for days,
but it is unlikely that you could pick the person in the painting from a lineup of similar looking people.

Realism done right, is the kind of art,
that once seen by the person in the painting...

It induces the urge,
to put palms of their hands on their temples...

And hold their head like that while smiling in fascination,
for a goodie-long while.

Afterword; and this is my private opinion,
but I suspect that here is a naming problem - a subtle distinction that has been missed.

Photorealism is closely connected to painting photographs,
Hyperrealism is a bit more artistic, more hyper, but there is more.

And I call it Super Realism,
unfortunately the world maybe calling it semi-realism, and that is just ridiculous.

Super Realism is is not just artistic,
but it beautifies and enhances human features.

Semi-realism will just enlarge eyes and perhaps make them fantasy based,
but Super Realism will enhance human features without unnecessary distortion.