la langue francaise est tres difficile

I'm reading a French play script at the moment. I have to ,because I'm going to design the set for it. Surprisingly, I'm not using my dictionary very much. Mainly because it slows down the process. I am amazed by how well it's going, and can't stop wondering where all those words that I apparently know are hiding when I try to use them in speech? And a more important question is: how do I make them move from that place to my mouth?
I want to be able to speak French, I really do. I hate the humiliation of being told to phone back another time when there's someone who can speak a few words of English around. It happens all too often. Or having to reply 'je ne comprends pas' when someone I don't know tries to start a conversation with me in the street or in the lift (that actually happens here). Not speaking very good French in Geneva really is a handicap. Hardly anyone speaks English. And yet I am too lazy to learn this language properly.
My recent discovery - that I actually have a much larger vocabulary than I was aware of - is because of this rather surprising to me. The fact that I have it also means that I should somehow try to use it I suppose. Or at least that I could.