If artists carried briefcases, this is what would be in mine...
Derwent Graphic Pencils
I bought my first set of Derwents when I was 13 after I won a $20 art voucher for a portrait I drew in chalk at school. I still have the original set, albeit dog bitten and very stumpy, for sentimental reasons. I have several sets of Derwent Graphics particularly in Soft and Medium (they also come in Hard). They blend easily with paper stumps and are agreeable to most surfaces, plus they are of high quality and compliment my drawing style. My favourite tones to work in are HB (excellent for those first marks on the page when you're feeling a bit nervous), 2B, 6B and 9B. I've just recently started experimenting with F, 2F and 4F which give a very soft finish (good for babies hair), but don't blend as well as the Bs.
I discovered these through an art book I was reading and haven't looked back. These are the best investment and are dirt cheap. The are literally just rolled paper which help to blend the pencil strokes into a soft finish. They really are the best way to create perfectly soft skin in a portrait. They have certainly helped to propose a more photorealistic finish. They come in different sizes and different textures. I just bought a mixed bag from my local art store.
Probably the most quintessential component of portrait art, the canvas (or paper) will play a large role in determining how the final piece of work will look. It's always important to choose a paper base that is compatible with your pencils and paper stubs. I use a 110gsm, acid free, medium toothed paper. It's textured enough to help add some depth to my drawings, but is smooth enough to allow for the use of paper stumps. This sort of paper is not ideal for water colours which requires paper with better density and absorbency. I did once draw a portrait on water colour paper just to see the effect and it resulted in a very rustic art work that had loads of personality, unfortunately it did lose that sense of realism which I like.
Sharpening, Erasing and Cleaning
It's always essential to keep pencils sharp when creating a portrait, especially when drawing the eyes and hair. I find that a good quality, steel sharpener is perfect. Electric sharpeners are good for avoiding an uneven sharpen as the pencil can be held perfectly vertical when sharpening, however, a sturdy hand still create the same effect. I used to employ art knives for sharpening pencils, but have since rejected them after the mess they make and the potential for injury (been there, done that!). Another good tool to have in the kit are erasers. My school art teachers hated erasers and said they had no use in the art room. I never liked my art teachers and have worked hard since to make the work of erasers a prominent feature in my portraits. It's best to treat your eraser like a white pencil and use it to create tonal highlights, a sparkle in the eye or wonderful wispy blond hair. My favourite toy is my electric eraser which spins at high speeds and is very precise in leaving its mark. Erasers are also good for their intended purpose of removing mistakes, and can save a beautiful piece of work from ending up in the scrap heap just because you made a small error. It's also a good idea to keep a small, soft brush (like a make-up brush) close by to use to sweep away the remnants of your erasing. Never brush your portrait with your hand as the oils from your palm can smudge and stain the work.
There are three other types of pencils that I love drawing with. Derwent Wash Pencils which act like a water colour, General's Charcoal which is bold and tactile, and Progresso Graphite which is so soft and goes on like silk. The picture of the eye in the photo above was actually drawn using all three pencil types. Ordinarily I don't venture away from Derwent Graphics much, but sometimes it's fun to explore other mediums.
Derwent Wash Pencils
All my drawings are finished with a fixative which ensures that the portrait won't smudge on the occasion it is handled or transported. It works really well and I wouldn't even consider leaving a newly finished portrait un-sprayed. It works on a range of mediums including lead, charcoal, graphite and pastels. One can lasts for ages and I bought mine from my local art shop.