There are several ways to discover what’s important to you. To help you help get started, I’ve listed some examples that brought me clarity:

Journal: after a couple weeks I saw the thread through my entries. It became very clear what experiences I considered 'very nice' and I wrote those points down separately.

Make time: I turned the above-mentioned points into appointments. For example: I noticed that I'd mentioned enjoying watching the Oprah Winfrey Show a lot in my journal. Several programmes had brought me new insights that inspired me to great depth.
So I decided to take the time to watch these shows daily.
From that point I also concluded that it was important to me to get new insights and decided to spend more time reading books that could help with this 'insight hunger'.

Collage: do you have a stack of illustrated magazines somewhere which in fact can go? Take one pair of scissors, thumb through the illustrated magazines and cut out, instinctively, everything you find appealing. A certain image, colours, expressions... do not limit yourself and cut out everything what you find attractive.
Glue this material on a large sheet and look at the end result a day (or more) later. Chances are that a couple of topics will clearly emerge!

Building on,