Where are you doing your test from,...?
If you are doing it from Lusaka, yes, you have something to worry about if you are really that nervous.
From what i have heard of the current drivers test in Lusaka, they are quite strict these days (Which is how it's supposed to be in my opinion), and the traffic coupled with some really rude drivers and the long route can surely make even i, who has been driving for almost 10 years become nervous...
So, some tips i heard from a few of my mates who went through it,...!(May Not accurate)
1. The basics,.. make sure you put on your seat belt before starting the car, check if your seat is adjusted well, rear view mirros, side mirros,...etc... (Assuming it's manual transmission)... drop the gear into Neutral, get your hand off the gear and start the car.
2. Each time you approach a stop sign (Be it the vertical post, or the white line on the road), you must come to a complete stop,(on a complete stop, others may emphasise on lifting the handbrake) and start all over again. This should be done even if the whole town has gone to Kenneth Kaunda Airport to receive the Zambia National team, and you are the only one on the road with your examiner. THe same applies when you approach the Pedestrian crossing. You might want to put hazards as well.
3. Don't drive above 40KM/h... You are a learner,..well,...ish... You don't want to give your examiner a heart attack.
4. Again, if it's manual transmission, attempt to take it all the way to the highest gear possible depending on what speed/part of the road you are on. The examiner would want to see if you understand this.
5. Show that you know what you are doing,...look in the mirrors once in a while,... act like you are a driver,...
6.Hold the steering with both hands, like a lady (No offence ladies)... Even when turning, do it so in a way your arms don't ''cross over each other''...
7. You are surely certain to fail on the first attempt,...Especially when they test you on the drums/cones, so get ready for next friday
8. Don't hoot near a hospital and some places i have forgotten....
9. All the best Bro!
THats all i can think of...!