Two tactics:
1. Do swear words. They are surprisingly easy to learn (.../..../../-)
2. Once you've mastered all the dots and dashes in the swear words, practice them by translating car number plates into morse.
I used the pooley's tutor for the PC once. It's REALLY good.
But why do you need to learn morse? Unless you're doing the CAA exams, you won't get formally tested on it.