Firstly this is not how I recommend all your performances should be planned. Still, I have done it a few times, so here are a few tips to get more out of the performance and hopefully not be so nervous.
1. Work with what you have.
Pushing yourself to the absolute limit to squeeze in all the preparation you should have done long beforehand can be exhausting and detrimental. Depending on how far along with the song and memorizing it you could be in for a string of long grinding nights to cram. Realize where you are and go forward to meet the deadline, prepare what you NEED for the performance. Without a doubt, there will be some things that you have to adjust, to work with the schedule if you have not at least finished production of the song you plan to perform. That’s all ok though. Focus on the people you will be performing too and the event itself. This can provide the mood of your performance and how you will decide to win the crowd’s appreciation.
2. Keep the Event Planner/Host Updated
While you are working up a sweat on those lyrics and music make sure the person that is allowing you on their event’s stage knows that you are as serious about this as they are. Tell them where you are, don’t get offended when they get concerned about your progress. Show them, answer their questions. Reassure them by showing them your optimism and confidence that you will get the job done. They obviously want you on their stage, act like you appreciate it and are excited to be ready in time.
3. Memorize and Practice
I don’t think it would have been acceptable to read off the paper for any of the events I have performed at… Outside of this just kind of seeming unprepared, it can also dull your showcase. What if you miss read a word, or don’t read every sentence, or worse; read it off beat because you are just trying to keep up. Honestly, that is really bad. Unless it is a part of your performance theme then it shouldn’t seem like you are reading off a script. Feel free and enjoy your performance and get the crowd involved. When you are focused on the performance then you can miss a line or forget to start on time and just bounce back without needing to find your place on a piece of paper. You can even add a small freestyle. Be spontaneous, and practiced.