how do you squirt ?

Okay, for years now I've watched countless videos and even looked up things on the internet trying to figure out if squirting is something some girls can just do or if it's a mind over matter thing. Some have told me it feels like you want to pee and others say you have to be extremely relaxed for it to happen. I guess my question is can I train myself to squirt or is it just something that some can do and others can't ?