Read descriptions of each sign and check which is dominant in your natal chart. It does not always have to be the sign in which your Sun is if it is in an intercepted house. Such house contains an entire sign, but begins and ends with other two signs and it usually does not manifest itself or is repulsive to you. After that you can connect the dominant sign with key archetype and planet.

Some natal charts will have only one planet in some of these positions and some more. For example, maybe your natal chart contains Pluto in Scorpio and that is why it is very important, but it must be used in a positive way because its energy is explosive.

Now there will be more to say about each planet. Try to determine which one is most important to you through descriptions given. Then connect it with a theme and area that interests you the most and your dominant archetype. Planet that is the ruler of your sign will be especially important for you. It affects the entire natal chart, so identify it based on sign of your ascendant.