Stuart bray talks about adding clay onto the face in small sausage like blobs, smoothing them down in the desired place with your fingers and adding more to create depth in areas. This gradually builds up to form the shapes you want before blending it all together using various sculpting tools. He explains, the more little dents you add and the more you cover, then the more everything will sit into place and look 'correct'. An acupuncture needle bent in half can be used for small detailing and drawing in dents. 

Advice: 

-Look at where the pores lie on the skin, it is important to know the directions of the pores on the skin, on old people they are more obvious and you can see where they lie, bigger more obvious pores can be seen on the cheeks at an old age. 

-Reticulated foam or a stipple sponge is good for dragging over the form to soften and reduce everything slightly. 

-A loop tool over plastic creates little thin lines and by varieing the pressure you create different depths with one tool, the plastic barrier between the tools and the clay prevents overworking and producing too much detail early. 

-By layering textures you create a natural effect and a natural wrinkling effect. Double the plastic over to mimimalise textures further and draw over it with various tools. 

-Sticking a needle into the clay and dragging it up slightly will create an open pore or goosebump effect, this displaces the material and creates natural bumps

-Soaking slithers of grated clay in lighter fluid for ten minutes creates a liquid plasterline slip. if you paint this or flick it over your sculpt it will create a raised bumpy texture. The lighter fluid that is on there will evaporate and the finish will be finer in detail.

-Talk will reduce the glare and show up any texture you already have, showing any imperfections in the pore texture and wrinkles.