"The players understand the position we're in and they realise the things we didn't grasp in the first two games," West Indies coach Bennett King told a news conference on Wednesday.
South Africa lead the four-match series 1-0. One of King's most pressing concerns was his team's shaky batting.
They capitulated for 194 in the second innings of the second test at Port of Spain, which South Africa won by eight wickets.
"We're working with the batsmen on shots and shot selection," King said.
"These players know their game pretty well and we've been stressing that they should remember their strengths."
Captain Shivnarine Chanderpaul felt the West Indies' major batting problems were in their minds.
"If we can improve the concentration, especially in the second innings, we should be able to get things right," Chanderpaul told a news conference.
The West Indies have suffered from a plague of no-balls in the first two matches, bowling 67 illegal deliveries. In the second Test, fast bowler Reon King was denied two wickets because he had overstepped.
King said the bowlers had worked hard to eradicate the problem and that the West Indies had also enlisted the help of the umpires for the third Test, Billy Bowden and Simon Taufel.
"We had the umpires come down and officiate at our net practice, and that was really good for us," King said.
The pitch at Kensington Oval in Bridgetown is the fastest in the Caribbean, but King said the West Indies would not rely on the conditions.
"We're expecting different conditions, but will still have to work hard for their wickets," King said. "We'll pick the best side in terms of who can get 20 wickets."
King said the West Indies were not despondent in the wake of their defeat in Port of Spain.
"In years to come people will look at the result and think it was comprehensive, but if you look at the intricacies of the game it wasn't an easy win for South Africa."
West Indies: Shivnarine Chanderpaul (captain), Courtney Browne, Chris Gayle, Wavell Hinds, Ramnaresh Sarwan, Brian Lara, Ryan Hinds, Dwayne Bravo, Daren Powell, Fidel Edwards, Reon King, Dwight Washington.
South Africa: Graeme Smith (captain) Nicky Boje, Mark Boucher, AB de Villiers, Boeta Dippenaar, Herschelle Gibbs, Andrew Hall, Jacques Kallis, Charl Langeveldt, Andre Nel, Makhaya Ntini, Shaun Pollock, Ashwell Prince, Jacques Rudolph, Monde Zondeki.