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