Leave the Sheet Music at Home
Students are tempted to bring their sheet music or lyric sheets on the stage as a crutch at student concerts. In most cases it's just nerves asking for that safety blanket. The end result is always awkward. Whether it's on a music stand or on the stage floor, your attention is drawn towards the sheet, even if you don't really need it.
So... leave the sheet music at home and trust that all of your hard work has helped to prepare you for this moment and let go of the terror of making mistakes. There is no such thing as a perfect performance. Mistakes are part of the performance. It's just up to you to turn off that negative voice and go have a good time... mistakes and all.
If you really DO need the sheet music, then you failed in your preparation. Use this as a wake-up call to prepare earlier and more completely.