I want to learn how to do all this stuff but I'm not an experienced linux user and I don't want to cause any serious problems on my N900 (brick it or something!)
I read through the instructions on the previous link that I posted and it all sounds a little complicated at the moment.
I have an Ubuntu 9.10 live CD available that I could use to partition my SD card but after that I need more clearly defined step-by-step instructions of what to do to patch and compile the kernel. (can I do everything from live-CD?

Is there really no other way to just prepare all the files, put them onto the memory card and launch it from within maemo so that it terminates maemo and loads from the memory card? (not affecting the maemo installation at all) (Then after pulling the battery it should just boot normally back into maemo)