Hi Emma
February is summer in South Africa so temperatures will be fairly warm - probably in the low 20s, on average. So i would pack for nice weather - t-shirts, shorts, light dresses and sandals. The temperature might dip a bit in the evenings so pack something warm as well.
As for spending money, you will need to buy one meal each day, plus drinks, snacks, presents and souvenirs. It's also worth deciding which of the optional excursions you want to do, and allowing a bit extra for those. I would say about £30 a day would be more than enough, plus any excursions you want to do.
Kind regards
Olly, your editor