Sulfur Hexafluoride 6 can be prepared from the elements through exposure of S8 toF2. This is also the method used by the discoverers Henri Moissan and Paul Lebeau in 1901. Some other sulfur fluorides are cogenerated, but these are removed by heating the mixture to disproportionate any S2F10 (which is highly toxic, unlike SF6) and then scrubbing the product with NaOH to destroy remaining SF4.
There is virtually no reaction chemistry for SF6. It does not react with molten sodium, but reacts exothermically with lithium.
Starting from SF4, one can prepare SF5Cl, which is structurally related to SF6. The monochloride is, however, a strong oxidant and readily hydrolyzed to sulfate.