Read some technical books.
Oxford Dictionary of Science is my personal fav; and what I used to get all technical. Reading literature, including fiction, works to get the vocab juices pumping -- make sure it's some good stuff, not bloody Andy McNab. Avoid newspapers/magazines/online journalism which are all sloppy and *****y (excluding the FT).
Big thing with academic law is it is very different from other academic disciplines. The writing style is very straight, direct and "brutalistic". No flowery stuff, no hiding behind polysyllabic words. Get to the point and get out.