When you had your talk in school you should have been given the Familiarisation Booklet which ToadMum linked to above. This shows you the type of layout / question paper / types of answers and also the types of instructions given in the actual test.
On the Tuesday before the actual test the children will sit a practice paper in their classrooms - it is just one paper and will be a different length from the 2 which they do for the real test. Based on previous years this will be harder then the familiarisation paper but easier then the real thing. The instructions etc in this will be the same as for the actual test.
The real test is two papers taken with (I think) approx 30 min break between them. The papers are 45 mins long. Based on previous years they will both contain elements of VR, NVR and Maths (maybe not NVR - I seem to remember when DS took it is was only in 1 paper??) but they will not have equal amounts of each in both. Expect the unexpected though so this could well be different in September. There will be no information as to the number of different sections or the timings of these sections. Some will be very short (based on previous years). The test will be over and done with by mid morning then the children all seem to spend the rest of the day eating cake with their friends and have forgotten all about it by the end of school
Your head teacher should be able to answer any other queries.
Many of the same questions have also been answered here: http://www.elevenplusexams.co.uk/forum/11plus/viewtopic.php?f=12&t=47188