Don't forget one of these...
http://www.caa.co.uk/docs/33/SRG1187FFenabled.pdf
You can also visit them and do it the same day by using their counter service, if you're in a hurry, still need all the forms though.
Public Counter Service Details | Personnel Licensing | Safety Regulation
..best to get there for no later than 0900 or you could have quite a wait.