[header] How to deal with mood swings (girls ) [title] Get some sleep. [step] Not getting enough sleep definitely affects mood swings. It can be hard to get enough sleep sometimes when your friends want to talk or hang out at night, but remember that it's important to get enough sleep so that you can feel your best. 
Of course you don't want to miss out on hanging out with your friends, but don't make it an every night thing. [substeps] It's suggested that teens get 8 to 10 hours of sleep each night.