These courses tend to begin with you being handed a timetable of lectures, and advised to attend all of them in order to get a feel for all the subjects before choosing those you'll stay with. The examination system allows you to ignore some aspects of the course. Project work, or essays will be have to be undertaken amidst the formal lectures and seminars; depending on the subject there may be demonstrations or supervised sessions in which you will acquire new skills.
The first six months of your course will remind you of undergraduate study: deadlines loom, lectures need to be attended, and occasional tutorials will take place. The courses tend to be intensive and it is hard to get a perspective on what you are doing until the second half of the year when you are engaged in your dissertation and are attempting to put into practice all the theory crammed into the first half of the year. If you don't pass the first half of the course then you may be asked to leave, the pressure is on, so perhaps you had better start some revision. Does this bring back memories? If it does, take consolation from the fact that roughly 85-90% of those on taught courses will pass them. The University probably wouldn't admit you if you weren't capable of passing.
The last part of the course usually allows you to get on with some individual research. At last. You can make all the choices. If you don't want to go to the library today because it is raining (or perhaps because it isn't raining), you are not going to be forced to do so. After all, you have just completed a fairly strenuous few months polishing off those essays and then madly cramming for the exams. You deserve a bit of a holiday.
Perhaps taught postgraduate courses are different to undergraduate study: no one is looking out for you. You have to rely on yourself the whole time. Planning is essential.
The problem tends to be that this crucial difference is not always made clear and it can take a while to pin point exactly what the course is being pitched at, and thus learning to respond accordingly. If it is at all possible to talk to others within the department who may have done the course previously this will certainly help in ascertaining what to expect from the particular course itself.
Most taught courses are one year MPhils, but there are also Certificates of Postgraduate Study or Diplomas available in some fields. These can all in appropriate cases count towards requirements for a PhD. Those candidates who finish their taught course may stay on to do PhDs but unless they were expressly registered for a probationary period will have to reapply through BoGS. There are a few postgraduate courses which cannot be counted towards a research degree: the Diplomas in Architecture (2 years), Classical Archaeology, Computer Science, Mathematical Statistics, the LLM (Law), Part III Maths and Theology.
Some courses require written exams to be taken. Strict rules govern the conduct of written exams, including the models of calculators permitted in exam rooms for some subjects. Rules are generally posted liberally around departments and colleges in the run-up to examination periods; it's usually wise to read them!