How would you do it since my way is bad practice?! I'm new, gimme a break.

I have been telling you the correct way all along; you just haven't paid any attention to it.

First, I would use a socket array instead of a single socket. Socket(0) will be the socket that the server listens on. Socket(1) will be the socket that the server loads and uses as the connection request socket thus becoming the communication socket. When the client closes his socket you need only to close Socket(1) and Socket(0) remains in the Listen state therefore eliminating the need to return to the server socket at the Socket.Listen.

Second, if I was to use a single server socket I would put a call statement in the Form_Load event which calls the server socket listen sub. Then on client closing I would put another call in the server socket close event to call that same sub thereby elimating the need for a timer event (which, by the way, you are the first programmer I have ever seen in all my years of socket programming to use a timer to trigger the listening state). Like this:
Code:
  '
  '
Private Sub Form_Load()
  '
  ' Do whatever needs to be done here
  '  
  ServerListen
End Sub

Private Sub ServerListen()
  Socket.Close
  Socket.LocalPort = 15151
  Socket.Listen
End Sub

Private Sub Socket_ConnectionRequest(ByVal requestID As Long)
  '
  ' Do same thing as you are already doing
  '
End Sub

Private Sub Socket_Close()
  ServerListen
End Sub
  '
  '
  '
  '
Above is for a single server socket. Using two sockets eliminates the call to the ServerListen sub in the Socket_Close() event.

Also, you should always have a Socket_Error(.....) event to trap any unexpected error(s) that might occur.

The above is the correct way. Maybe not the very best since I have seen much better socket programming but for a simple application like yours the above is the way to go. Using a timer is pointless and your boss would probably make you re-write your code. If this is only for you and you alone then you can do it anyway that siutes your fancy but I am just trying to help you get it done right from the start.