Step One, you should apply for a tourist visa before you land. Once you have your visa, the fun begins.
Step two, when in Zimbabwe it's best to hire a vehicle for all the days you will be there. Also get fuel coupons from the reserve bank in Harare so that you don't get stranded concerning fuel.
Step three, get yourself a Road Map.
Note that you need to do some early bookings for the places that you might need to visit.
You might need a travel companion to help you where there is need of translations and so on.
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