One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6)(7,11)(8,10)(9,12)(13,14,17,18)(15,20,16,19)(21,22,24,26)(23,25,28,27)(5,7,10,12)(6,11,8,9)(14,18)(19,20)(21,22)(23,27)(24,26)(25,28)(2,3)(6,8)(7,12)(13,15,17,16)(14,19,18,20)(21,22,24,26)(23,25,28,27)(1,3,4,2)(5,8,10,6)(7,9,12,11)(13,16,17,15)(14,20,18,19)(21,22)(23,25)(24,26)(27,28)(5,9)(6,7)(8,12)(10,11)(13,14)(15,19)(16,20)(17,18)(21,23)(22,25)(24,28)(26,27) involution — undirectedA 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.