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