In charades, sequences of gestures can come in any order.
How does word order get established in the first place? In charades, sequences of gestures can come in any order. But if we use charades to convey who did what to whom, some orders may, perhaps by chance, come to be more prominent. Eventually, one order might even become entirely standard. Once a particular order (such as SVO) becomes established, it will tend to stick—after all, if we violate the expected order, then, other things being equal, we are likely to be misunderstood. And historically, languages do indeed seem to shift inexorably from so-called free word order patterns to increasingly rigid word orders.