Gets locked off the network?

Can you give me some methods on how could I keep from being the first and only person that gets locked off the network? Because I shared a network with some several users. And there are different machines that could access my network regularly. Those are the:
Ø 2 Mac book pros
Ø 2 laptops
Ø 1 Mac book
Ø 1 desktop
Ø 1 XBOX 360 that runs live
Ø 3 iPods
Every time I m using the network I can’t connect easily due to some persons connects to my internet. And I want that I would be the First that could connect the internet easily and stop the connections when I’m already out. I want to access my network easily.
