Easy all you got to do is have a look at who is on at the moment, and write those names down on a piece of paper, so you know who was on at the time....Just in case there are a few of you on at the time...:D
Then all you got to do is watch, and slowly there will be pattern to as who has been negging you....
And after all it's the biggest compliment there is, because they consider you a big threat....And that is good. :D
