You forget everything that you don't spend time to remember. So it takes time.
The easiest time to remember a dream is right after wake from it. This is why I wake many times throughout the night (like cooleymd), because then you can "easily remember many dreams. They are still going to take some time and practice, but if you spend the time, you will start remembering your dreams more and you will start having all sorts of dreams.

I use this tech for most of my dream related needs
http://www.dreamviews.com/dream-sign...cro-wbtbs.html

But that actually came from this:
http://www.dreamviews.com/dream-sign...m-journal.html

These I have found amazingly important in both recall and LDing.