Confront the things that scare you & stress you out. Think about something that makes you uncomfortable. Something that stresses you out a little just thinking about it, like maybe calling someone on the phone or even just saying hi to a cute guy or girl. Now go do that thing. Then think about something that's just a little bit scarier or more stressful than the last thing you did. Do that thing. Slowly push yourself outside your comfort zone more & more. After a little while, think back to that very first thing you did & it won't be half as scary as it was at first. If you can maintain a positive attitude throughout, you'll come out the other side stronger than you were before, & most likely more fluent & confident.