On several trips to Europe and Africa, my little tricks were: the minute you get on the plane, set your watch to
the time zone of your next arrival (so, if you're landing in London, switch to that). Then, when you get on the plane to Nairobi,
do the same again. And act like you're on that time--so sleep when you should be for your destination. So, if you're on a
flight from London to Nairobi during the day, stay awake. Since it sounds like you'll be on that flight during Nairobi night,
I'd pop an ambien and enjoy the extra sleep. When you arrive, again, take a nap if you need, but try to get your body clock
moved over--sunlight is the biggest thing, it makes a huge difference!
Try to acclimatize yourself to going to sleep in the days before departure as early as is possible. Too bad you are departing
in the evening. Our departure in August is at 3 pm and so I will take an Ambien and should be asleep by 3:30 (It drives my
wife crazy how fast I can fall asleep)
So go to sleep as soon as is possible after departure. Wake up as early as is
possible and try desperately to stay awake until you get on your redeye from Europe. Take an Ambien about a half hour before
take off and try to sleep as much as possible.
After arrival in Kenya try to stay awake as much as possible during
the first couple of days. If you take a nap during the day, do not sleep more than 30 minutes, otherwise the body gets into
a detrimental sleep mode.