A busy handbag : A busy mind

I would like to be able to pack my bag this light each day, this was a weekend day back visiting my parents. I was popping out the house for a very short amount of time and it was delightful to not carry much. Usually adding my gym kit and work essentials turns my bag into one if not two, shoulder aching bags. Along with a bag filled to the brim I am also carrying around my mind, which is packed full of ideas and constantly looking into the different pathways and opportunities that I have at my feet right now.
At the moment I am trying to figure out which path I am interested in, my Business Studies degree has opened many doors, too many some may say. I need to pick one of these doors to go through and find out what is hiding behind it.
I keep being pulled towards advertising and marketing, the two fields which first made me pick Business Studies in college and at university. I wont lie to you, I had a sneak peak behind these doors.. and behind them is more damn doors. A door towards a masters, a door towards work experience and a door full of application forms. 
I am just trying to decide which step to take next..
Do any of you work in advertising or marketing.. I would love to hear any tips you have or just a little about what you do.