How to write a 1st class law essay?

Read the essay question or topic carefully and make sure that you cover every bit of it.
Read judgments in preference to commentaries on judgments. But take note of any scholarly articles which your tutor favours.
Read as much of the relevant reading list as you can, but it is better to read most of items on the list with care than all of the items on the list in a hurry.
If reading legislation, read every word in every relevant provision, and seek to give meaning and effect to every word. Pay close attention to definitions.
Write in the active voice. Use short sentences and short paragraphs. Avoid adverbs and adjectives. Check grammar, spelling, and punctuation.
The way to write well is to read a lot. To obtain a good writing style, read literary novels, The Economist, and judgments written between approximately 1880 and 1990. Note in particular the judicial writing of Lord Atkin, Lord Denning, and Lord Justice Laws.
Give the essay a beginning, a middle, and an ending. Pay attention to the word limit if there is one. Set out your references in the manner requested by your university.
Support each proposition of law that you advance with an authority, be it a case, a statute, or the opinion of a respected scholar. Deal fairly with any authority that is adverse to the position you are arguing.
Try to avoid an essay which consists of "on the one hand this, on the other hand that". Take a position and support it.
Good luck!