I've just opened this thread (I know it's been going a long time) but please may I repeat the fact that older people, and that includes me, have a lot more trouble remembering the words than years ago. I hope I am still a good singer, and I do make large efforts to learn words, but I simply cannot rely entirely on memory, even for songs I know well.   Far better to have that sheet of paper handy and produce a good performance. I'm not suggesting for one minute that you rely on it entirely and certainly no mobiles (ghastly). One tip I've found useful is to keep a finger on the verse you're singing so you've got instant access to the next line if needed without slavishly reading the words. After all, you need to keep an eye on the audience to make sure they're listening! So guys, please, let's have a little tolerance for us old folkies!