We have books given to us by the farm assurance chap who comes every year to inspect the farm for Farm Assurance status- all of our cattle records are now kept on a computer programme that the farm bought earlier this year but the sheep records are still on paper- I think you can get similar from eblex but they are worth getting hold of a proper booklet rather than just using a notepad- have different sections for routine treatments like worming/flystrike, routine actions such as dehorning, docking, castrating, sheering, and then a section for medicines administered.