One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6,9,7)(8,11,12,10)(13,14)(15,20)(16,17)(18,19)(21,22,27,25)(23,28,26,24)(6,7)(8,12)(13,15)(14,17)(16,18)(19,20)(21,23,27,26)(22,28,25,24)(6,7)(10,11)(14,19)(15,16)(21,24)(22,26)(23,25)(27,28) involution — undirected(1,2)(3,4)(5,7,9,6)(8,11,12,10)(13,16,18,15)(14,20,19,17)(21,25,27,22)(23,28,26,24)(5,8)(6,10)(7,11)(9,12)(13,17,18,20)(14,15,19,16)(21,26,27,23)(22,28,25,24)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.