So it's not that hard to figure out your in a dream. In a dream try to do something you wouldn't normally do. Like flying, as in not on a airplane, or anything like that. Here are more examples.

• Hold your nose closed or go underwater, if you can still breathe then you are dreaming.
• Try to jump, if anything strange happens you are dreaming.
• Read stuff, if small print changes as you look away or are looking you are probably dreaming.
• If your vision is perfect but you don't have perfect vision, you are probably dreaming.
• Examine your hands; they can usually be pretty obvious. Sometimes changing color and size or growing an extra finger.
• The time, always check the time. Clocks will change at random times, have improper numbers, or simply change as you look at them.
• Try to visualize using powers, in a dream they will often manifest themselves fairly quickly.
• Try a light switch here and there; they usually don't work in dreams. This isn't an absolute however, and they do occasionally work.
• Check your reflection; usually your dream will have trouble keeping that constant.
• If you close one eye, can you see your nose? If not you're probably dreaming.
• Try to remember things like; why you are there, how you got there, what you were doing 1,2,3 or hours ago... etc.
• Try biting your lower lip and really experiencing any minor pains.
• Be creative and just do things you can't do while awake.

I hope that helps.