When a registering a channel, you decide the name you would like if it
is not registered by another user, you would join that channel.

/Join #channelname
or
/j #channelname


You then will want to register the channel.

/msg chanserv register #chan channelpassword Descriptiongoeshere
or
/cs register #chan channelpassword Descriptiongoeshere

For more infomation:
/msg chanserv help register

Please keep in mind of security chat's rules and policies before you
decide if you want to make our network your home.