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