Quick question since my memory sucks...

When I enter via Global Entry and get my slip, there is no "line" for me. In the past, I've just walked up to an Immigration officer even if they were speaking with someone else and handed them my slip (I wasn't trying to be rude - I actually thought you just hand it and off you go). Perhaps it's better to wait... but where? If I wait by the machine that provides the slip, other people walk up to the immigration officer and I just stand there. But if I walk up when he/she is clearing someone else I come off as rude. What is the policy here? Do I just wait til it opens then aggressively walk up beating the next non Global Entry person to the officer to give him my slip?