How can I sneek out tonight?

okk soo i have no lokk on my door an ther is an alarm system and my mom puts it on every nite so if i open one dooor she'lll catch me lol. i jus want to sneek out from the window or something..idk what to do and if i turn of the alarm it makes a noise...soooooo idkk help please! ohh yeah and im grounded so i cnt do anything!:/