Google around for "hyperrealism", the techniques are well-documented. You can see in a few pictures the existence of a grid. It was originally used to transfer

Google around for "hyperrealism", the techniques are well-documented. You can see in a few pictures the existence of a grid. It was originally used to transfer/scale drawings, but is also used as a substitute for untrained eyes who would struggle to get fair proportion otherwise. Then the rendering itself relies on pencils that are sharpened quite thinly: the thin lead will be less sensible to the paper grain, and provide a smoother result. If you want more texture, used a duller lead. An even softer texture, use a brush or a stomp. Generally, you'll want to draw quite big, so as to have enough room to articulate the details. Finally, the key difficulty, "trick" even, for hyperrealism, and for fine-arts in general, is patience: good results are often produced with plenty of time.