Making your own Lag switch is cool, but you could try a software lag switch first if you don't want to waste the time. I use one called Laggsta and it works well for me - I haven't got banned but I hear you can get banned if you get caught
I made an inline one and it didnt work, just kept saying ethernet cable disconnected, so I would try the softwear versions.
And yes you will be perma console banned if you get reported or caught using one.