Now, when you finally joined the channel.
First thing you want to do is to change your nick.
/nick yournick

Next, you want to register your nick, so that noone will steal it. Type in this
/msg nickserv help
It would we wise for you to read this.

On with the registering. Type this in.
/msg nickserv register help
Read the messages there. Should be self explenetory

When you recieved your pass follow the instructions in the email
Now to identify
/msg nickserv identify yourpasswordhere

You can ghost a nick that you registered. Its usefull if your internet crashed and you want to "kill" the ghosted nick. Typr in this
/msg nickserv ghost thenickyouwantoghost yourpass

Grouping
If you use multiple nicks, you can group them. Its way faster than registering each nick. to do this type in
/msg nickserv group yourmainnick yourpass