As we're sure you'll be pleased to know, the Students' Union is a democracy, which means that every sabbatical officer, council member and student representitive are accountable directly to the student body.
The Students' Union exists to represent all students at the University of Manchester. It is autonomous from the University and is democratically controlled by students at all levels. All University of Manchester students are automatically members.
So, to get involved in doing the right thing and holding your representivies to account, have a look at the links on the left hand side of this page.
Or, why not stand in union elections? Keep an ear to the ground and look out for accouncements and emails about when the next elections are, and who's eligible to stand for what!