Body language - signalling in conversations

[JohnClay]

I rarely make eye contact with people in conversations and have only recently realized this. The eye contact I do now is done pretty weirdly since I’m not really sure what to do (and also it is scary).

I’ve read some body language books and was also reading this:
http://www.bremercommunications.com/Eye_Contact.htm

I’m not sure about these parts:

…When you are done [speaking], grant permission via eye contact to the person who has signaled his intention to speak next…

I guess the speaker grants permission to the next speaker by simply making eye contact, but I wonder how the next speaker signaled their intention to speak? It would have to be more than mere eye contact.

…In group conversations, you have to signal to all others that you want to speak…

Again, what is that signal?
Thanks.