/ns, /cs, /bs/ /os. ext

[Callumlord]

How do I get the /ns /cs /os /bs ext??

I know it is alias but how do I do it?

C

[Jobe]

If you're using Anope you simply add the following to your unrealircd.conf:
include "aliases/anope.conf";

There are also various default aliases for a couple other services packages, just take a peak in the aliases/ directory to see which.