Timing the market is near impossible.
The Rand could go up or down, and the index could go up or down.
There are two trains of thought:- the momentum methodology (employed by ETFs like NFEMOM, for example) is based on the premise that shares that are going up strongly will continue to go up. The momentum methodology says now is an excellent time to buy. On the other hand, the value methodology (employed by ETFs like NFEVAL for example) say you should buy when prices are cheap. This methodology says you should wait.
I personally do Dollar-cost averaging by buying an equal amount monthly. This way, you get the best of both worlds. It might be something for you to consider (ie. buy R2k per month for three months). This way, whatever happens, you minimize downside risk.
But otherwise, as for your question, with all short-term decisions in the market, you may as well roll a dice.