1 - First and foremost, don't be afraid of it. You need to use it. Every. Single. Day. Use it to browse the web for example. It'll help you get used to the sensitivity (practice highlighting sections of text), and all of the features of the pen. Some suggest that you should hide your mouse, so you're forced to only use your tablet! Through daily use, it should become an extension of your arm, and begin to move naturally.
2 - Play with it. Mess around with all of the settings your tablet has to offer. Not only will it help you find the settings you're most comfortable with, but it'll teach you what each individual part does. Also play around with it in your chosen drawing program (Photoshop / SAI / etc.), you'll learn more about your tablet and how it reacts to the program's settings (which may be different than what you're used to) - you're undoubtedly going to want to test the Pen Pressure setting within the advanced brush menu.
3 - Doodle. By doodling you're not only using it, but you're creating shapes (no matter how indistinguishable). Perhaps even start a new art project and only use your new tablet.
4 - Write with it - heck, even sign your name. We've been writing for almost our entire lives, we know the motion of each letter perfectly, and our signatures barely change throughout out life - so replicate that with your tablet.
5 - Read tutorials about your tablet. Learn tips and tricks from those who are used to using it every day.
6 - Still having troubles? If you've made the leap from drawing traditionally to drawing digitally, why not stick a piece of paper over the tablets drawing area. It won't effect the pen (in most cases) but it will give you a more natural drawing feel and help you in your transition.
For further reading, I highly recommend visiting this site, it offers some really useful exercises you can do to get yourself used to your tablet: How to get used to your tablet.
!