Making trade mark infringement cases should always start with a letter, then the follow up formal document in the appropriate legal format setting out the causes of action are crucial and should not be attempted lightly. This formal document making trade mark infringement cases is called a pleading.
There are different styles and methods of preparing these pleadings. Once the substance has been covered then differences are mainly down to style. In the recent case of Enterprise v Europcar incidentally addressed the subject of how pleadings are prepared when making trade mark infringement cases.