Have a look at the CAA website Safety Sense Leaflets
.
http://www.caa.co.uk/srg/general_avi...sp?groupid=231
The Radiotelephony one runs through an example RT practical.
In the exam you'll most likely have to do A/G departure or arrival, get a FIS, get transit through controlled airspace, Mayday, relayed Mayday, VDF and MATZ penetration, so make sure you can do all that.