How to make the most of my internship?

So, I started the internship in Germany two weeks ago and now I am wondering what I should do to make the most of my internship....

The firm is apparently highly regarded in the industry and has several offices around the world. 95% of the people working at the firm have at least 10/15 years of experience and have worked for BBs.

The internship is not structured at all and I can pretty much do whatever I want to do although I am officially interning in their Cash and Derivatives Sales Trading unit.

This is what I have done so far:
Bloomberg Seminars
Steel Industry Transaction Multiples
Week Aheads
Currently managing a paper money portfolio using technical analysis (the head of derivatives acts as my "trader"). Its an ongoing thing that he wants me to do.
Asking questions - its been a hectic two weeks so only few have been willing to answer questions and let me sit with them
Coming in at 06:15 and leaving past 9pm
My boss told me the other day that he is preparing some stuff for me to do (mainly spreadsheets - testing and correcting).

BUT what can I do to really convince them that I am interested and that I am not a slacker (because that is what I think I come across as right now). What can I do to dazzle them?

Phil