I don't think there's an "offical way" of doing it, it mainly depends on your skill level & tools.
Did you see this thread, you got a lot of links to go through and read, there's listings for x25 & 9mm (both are basicly the same)
You could also do a gas operated set up if you don't want to mod the bolt.
I've also seen someone that pinned the bolt in place instead of welding it so it can be taken apart fairly easily in case something needed replaced.
OH and there's a good thread by doubletapme on Weapons Guild, if you want to see it I'll link it or post some pics, it's a gas setup.