Fuji,
Please add into your diversion checklist a check that you are not going to cross controlled airspace, danger/restricted/prohibited areas, any relevant NOTAM'ed areas, etc. Either using your GPS (if it is up to date) or your chart.
Also, what radio frequencies are you going to use, both for the en-route phase of your diversion and the arrival? Almost any GPS will be able to give you the relevant frequencies (so long as the database is up to date, of course), usually with just a couple of button presses, but do you know which buttons to press? In a high workload situation, in bad weather?
It's well worth knowing how to really use your GPS before you set out!
FFF
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