There are many ways you can do that , some state moving your Bitcoins into some safe wallet getting the pass phrase out if your wallet , the thing they ask you to write down when you make a wallet initially and then making a wallet with the same pass phrase in a wallet that supports the fork , like coinami or something and then you may or may not receive your coins actually .
It's like a fast DIY but you know the value of Bitcoins diamond is just around 1$ , don't risk your privacy , I mean even if you had like 1 BTC you will only get 1$ thus just buy them.
Moving his Bitcoins out is a must and once that's moved to a different wallet there's less risk at that point. The only thing he'll risk losing if he uses a service are the other forked coins under those addresses. It's like a fast DIY but you know the value of Bitcoins diamond is just around 1$ , don't risk your privacy , I mean even if you had like 1 BTC you will only get 1$ thus just buy them.
Also there are official wallets listed on the main site that only supports their coin better to use those than other wallets that supports several forks if you're doing it by yourself.
