hi! i took gcse drama , so i thought i i could help. in terms of the performance, there are key KEY aspects that you need to include according to pretty much any board's criteria:
1. USE. SPACE - try not to spend too much time on the floor, but use levels and move across the stage as much as you can with your piece.
2. use exaggerated gestures, facial expressions, volumes, pitches (don't be too ridiculous with it though obv haha).
3. even if your character is supposed to be nervous or shy, make every gesture or expression a CONFIDENT one - refrain from overly naturalistic acting.
4. show a RANGE of emotions - this will demonstrate the scope of your acting skills to the examiner. if your piece is mainly sad, have one moment where the character gets furious. if your piece is excited, have one moment where they are suddenly shocked by some news. you know the vibes.
5. EYE CONTACT OMG. eye contact is one of the most powerful things in drama and use it wisely! look in the corner of the room, at your feet, stare directly into an audience member's eyes. this is very effective
hope it goes well! good luck xx