From my limited but successful experience:
Get the Never Get Lost
book (RANT covers the software side):
http://www.nevergetlost.at/index.asp?sprache=english
at this point play with the Luiz Monteiro online simulator:
luizmonteiro - Aviation Calculations Home
Get hold of RANT:
Oddsoft Ltd
Read Instrument Flying by David Hoy
Instrument Flying by David Hoy, 9781861267498
Watch The Complete JAR Instrument Rating by John Pullen - Available at
www.TransPooleySportysEmporiums.etc as DVD.
Then take your poor overloaded brain to be soothed over Bedfordshire with Bonus Aviation, Cranfield.
Simples.