Barnes was described as more than six feet tall and maintaining an erect posture with wide shoulders, a deep chest, long arms and strong legs – in John Arlott's view, "perfectly built to be a bowler". He bowled right arm fast-medium but also had what Arlott called "the accuracy, spin and resource of a slow bowler". Barnes' high delivery provided him with a lift off the pitch that forced even the best batsmen to play him at an awkward height. He was clever at concealing his pace and could produce deliveries that were both appreciably faster and slower than his usual fast-medium pace; and could bowl an effective yorker. Barnes considered himself essentially a spin bowler as he bowled both the off-break and the leg-break, but at a fast pace. Although technically formidable, Barnes allied his skillset to a hostile persona and great stamina which, Arlott says, "were reflected in constant, unrelenting probing for a batsman's weakness and then attacking it by surprise, each ball fitting into a tactical pattern". In Barnes's era, the same ball would be used for the whole of a team's innings, with no new ball, although bowlers were assisted by the unpredictability of uncovered pitches.