"The biggest thing in art, is getting the proportions right."
-- Abraham Lincoln
To get the proportions right you should use an office projector,
see if a Pico Projector is right for you, they are often about $50.
There are other ways you can transfer proportions,
print your subject on paper, and some graphite on the back of your printout.
Then put your graphite backed printout over your artwork paper,
and mark all the important spots with a pencil, the graphite backing will leave gentle marks on your art paper.
Above all you need a good photo, preferably a portrait, possibly your own,
but you have to make sure, that your light source is casting some shadows.
Take a look at Mona Lisa, look how dark her neck, and areas above eyelids, look at her nose,
it is both completely submerged in the shadow and casts it too.
This is no coincidence, arranging light and shadow before making a portrait is a huge deal,
if there is just soft light shining straight at the face, you will not be able to speak with shadows.
Start outlining where all the shadows are,
use art pencils, they differ in intensity and hardness.
Pencils marked HB, H, 1H, etc are hard and thus leave a light gray color on paper,
pencils marked B, as in 1B, 2B, 3B and so on, are soft and leave a deep rich dark color when used.
So you would use maybe 4B for Mona Lisa's eyes,
but HB to draw her hair, or veil - or her eyebrows, if their absence bothers you as much as it bothers me.
Don't press your pencils into the paper,
don't scar the paper as that is hard to erase.
And use a Blending Stump,
to smooth everything out.
You will also need a drawing board,
so that you can take your outline sketch outside, maybe a coffee shop, or a park, or a lake.
Drawing at home is very difficult,
art is about adventure, and nature.
If it is too difficult to go outside a little bit,
then go all out, take a picture of an interesting building by a bench you can sit on, prepare your sketch...
and go to the bench where you took your photo,
now that your sketch has all the proportions right, you can just look at your subject without photo reference to add the shades and blend all the shadows.
Sometimes people come around, all enchanted by your art,
and sometimes you meet another artist, everyone is always very nice and sophisticated.
The thing that creates an artist,
is being - out there - doing art.
go right now, and don't stop.