Xulu, released by Chiefs at the end of last season, has been handed a three-year deal by the Team of Choice.
Coach Fadlu Davids believes the signing is a show of intent from Maritzburg and Xulu is eager to adapt to the new club and perform well.
"The very first main for me is to try and concede less goals and I think that is what I'm going to be focusing on," the 25-year-old said.
"Obviously I haven't been training in a while and I have been training on my own and it's not the same. But first things first, I have to gel with the club, I have to see my new teammates, I have to get along with the playing personnel of the club, which is not going to be difficult for me because I'm one player who strongly believe in his abilities.
"I don't think that it will take much time for me to adjust at the club."
Meanwhile, the former FC Rostov defender, who has four caps for Bafana Bafana, still believes that he has a future with the national team despite not getting a look in since his 2015 return to Chiefs.
"I'll go back where I just mentioned that I'm one player who believes in himself," he stated.
"And there's only one Siyanda and Siyanda, given a fair chance, can always compete."