I use high quality acid free 250gsm heavy weight paper that has a smooth finish.
Acid free because this will ensure against yellowing over time and your portrait will stay looking as good as new for hundreds of years and smooth because this gives better quality tone changes.
I also apply a fixative spray in sevral coats when the portrait is finished to guard against smudging and it has built in uv absorbants to protect against light damage.
Faber-Castell 9000 Graphite Pencils are what i use for the majority of my portraits as i find them to be very well made and always a smooth graphite with no gritty clay particals that can skratch the paper.
The graphite is always central and even with a uniform grade throughout.
Well worth paying that little extra for.
I also use fine mechanical 0.5 technical pencils for some of the very fine details.
The leads used are Faber-Castell technical and for the darkest areas i use Derwent Graphic 9B pencils.
Shown in this photo- Derwent 9B pencil,Graphite stick,Derwent Electric eraser,putty eraser,Tortillion blender.
The Graphite sticks come in a full range of tones from HB to 8B and are used for shading large area's and the Electric eraser is used for detailed highlights.
The Putty eraser is used for light tone highlights.
I use Winsor & Newton 250gsm extra smooth Bristol board, it is acid free archival museum grade fine art paper.
I use Winsor & Newton Artist's Fixative spray that has built in uv absorbers to protect the work from light damage and guards against smudging.