How to let my mum let me stay at my friends house for a few days? 10 POINTS?

Well my friend is moving to a place 2 hours away, and her dad has offered for me to stay with her and her dad for a few days, and like help them paint the rooms and set up and say bye to her because i wont be seeing them for a long time, and im just started school holidays, and im doing anything, and my mum she isnt letting me go and she just says no :( their going tomorrow, so i have till tomorrow morning to convince my mum and my friend is with me tonight, but yeah please i need help!!! thanks :)