How can I kick higher?

Well I'm no Kung foo master but I am a cheerleader. In my personal experience, it helps to stretch a lot! Stretch ur legs really well at least twice a day. Go as low into a right split as u can, be sure not to keep going lower if u r experiencing extreme pain just stay where u r comfortable gradually making ur way down. I know u r probably tired of everybody saying to stretch but trust me that's the only way. Hang in there, if u follow my advice you'll get it faster than u think