Rules of Feminism 5: Educate Yourself
You are (presumably) not in school any more. (If you are, kudos for your interest in feminsm!) Here in the adult world, there are no on-demand educators unless you start throwing money around. Instead, you have the might of Google and most of the knowledge and wisdom and history of the human race at your disposal on the Interwebs. So, with that in mind...
Education is YOUR responsibility.
If you feel like you're ignorant about a particular topic, or someone flat out tells you you don't know what you're talking about, YOU need to go fix that problem. You have the tools, and you have no excuse not to use them.
This is especially true, by the way, if you grew up somewhere that was missing a particular type of bigotry. Take Ireland, for example, where I was born and raised - it was 99% white and Catholic in my childhood. I only saw black people on TV and in the movies, and racism was something that happened years ago in America. Does this mean I'm not racist? Hell no! It just means I'm ignorant in a different way, and I have got to fix that myself. Most of that involves reading and listening to people of color, especially women of color, on Twitter and blogs and whatever.
Women and people of color and minorities tend to get this kind of stupid ignorance-trolling shit all the time. Like, idiots show up in their comments or Twitter feeds or whatever 'asking questions' and playing devil's advocate and generally being dicks for the sake of it. Go ahead and tell me how soon you'd lose your shit if you had to constantly deal with ignorant fuckwits, and it's damn near impossible to tell which ones are sincere and which are just being assholes. So don't add to that. Do your own damn homework before you return to the conversation.
Above all else, remember this: the oppressed have got enough to deal with as it is, and expecting them to explain the nuances of how the world fucks them over to your perfectly-capable-of-using-Google ass is plain offensive.