What to pack
Neutral clothes, a warm layer, and a soft bag if you are flying between camps. The rest is detail.
Clothes
Pack colours that disappear into dry grass: khaki, olive, brown, sand. White and black stand out on a drive, and bright blue is a favourite of tsetse flies in some valleys. Skip camouflage patterns. Several countries treat military-style clothing as something civilians should not wear.
Mornings in an open vehicle are cold in the dry season, even when the afternoon is hot. A fleece or a windproof layer earns its place. So do a hat, sunglasses, and a scarf you can pull over your nose on a dusty track.
Long sleeves and long trousers are more useful than shorts once you are out of camp, because of sun and insects. Evenings at a lodge can be smart-casual. You do not need formal clothes. Towns, villages, and gorilla briefings are easier in clothes that cover shoulders and knees.
Kit that changes the day
Binoculars matter more than a second camera lens. An 8× or 10× pair is enough. If you photograph, a zoom that reaches into the distance is more useful than a wide-angle, because you will not be leaving the vehicle to get closer.
Bring any medicine you already use, plus what the travel clinic recommended. A small torch or a phone light helps on unlit paths. A reusable bottle is easy to refill at camp. Cash in small notes still matters for tips and for shops that are not on a card machine.
The bag
If the quote includes a light aircraft, pack in a soft bag. Weight limits are real, often around 15 kilograms of soft luggage in a pod under the plane, plus a small day bag. Hard suitcases and long tripods are the usual problem.
Laundry is available at many camps, sometimes for a fee. On a ten-day trip you can pack for five days and wash, which is what makes the aircraft limit possible.