sometimes when trying to remember a script, I will take a piece of paper that I can't see through and place it on what I'm trying to memorize a line at a time slowly dropping it as I'm able to recite the next line. That way I am able to look when I need to but I cannot glance at it while I go which makes my feeble old brain engage somewhat more than it would if I could cheat. Context and motivation are the best keys to success here I think. If one knows the story one can sometimes fudge the words and it still comes out allright. Key verbs and the ever popular favorite turns of phrase are very helpful. One must not, except in cases of extreme informality take the paper to the stage. Bad form!! We must relate the story to the folks as if it were the first time we had the chance to tell it. There is much to be learned from the performers(singers) face. We must see it. Abject fear is often what the audience sees and they love it. There is certain empathy there. Empathy is much better than sympathy which is what the audiance feels when they see the paper. Even though we've been practicing for days, it's the first time for them and I think there's a certain ease that that fact can give you as you prepare for the telling. The audience is ready to be taken on a journey or they would have stayed home. Know your stuff and take them there. It's the highest honor. Man, am I full of shit or what?