I too fly a lot. But I can't say that I find the safety instruction card terribly helpful - partly because unless you know what it is trying to tell you, you're lost. For example, it shows the 'brace' position without saying what it is or when it's to be adopted.
So although it may be of some help to native language speakers, the safety demonstration is probably more use. Having said that, I was on one flight in the US some years back where FA's accent was so broad I couldn't understand her!
One would expect that the 'brace position' would be pretty self explanatory and it would be used when told to by the FA's
Seriously people, if you don't want to listen to the safety brief, don't. But watch out if you get in my way or the way of other, more reasonable people when we are trying to get out of a burning or sinking aircraft.