For the mathematics, the required textbook is Mathematics for Economists: An Introductory Textbook, 2nd edition. Malcolm Pemberton and Nick Rau.
You may leave aside chapters 22, 23, 24, 28, 29 and 30.
You must work through the rest of the book, solving at least the exercises for which solutions are given at the end of the book.
Chapters 1 to 10 will most probably be familiar material.
Chapters 11, 12, 13 and 25 cover matrix algebra and systems of linear equations, which you will need in econometrics as well as in microeconomics and macroeconomics.
Chapters 14 and 15, on functions of several variables and implicit relations, you will need both in macroeconomics and microeconomics.
Chapters 16, 17 and 18 deal with optimisation, which is essential again in macro and micro.
Chapters 19 and 20 deal with integration and its role in economics.
Chapters 21, 26 and 27 deal with dynamic optimisation, which is essential in macro. For some of you, dynamic optimisation will be new, it is particularly important that you familiarise yourselves with the concepts of these chapters.
For the statistics, you may use the textbook Introductory Econometrics: A Modern Approach, 4th edition. Jeffrey Wooldridge. You should work through the appendices and then through as much of the book as you can. It is intuitive, engaging, and accessible.
If you have a textbook that you particularly like, you may of course use it instead or in addition to the above. Make sure, however, that you cover all the relevant material prior to the start of the course.
Former students have found this material very useful:
http://ocw.mit.edu/courses/mathematics/http://www.ucl.ac.uk/economics/graduate/course-list/econg100