Contacting a Professor about a possible Ph.D. During my Masters I wrote and published a series of three research papers, which I presented at 3 different international conferences. 

After my last presentation/talk at the 3rd conference, a Dean from an Australian university approached me and after talking for some time he gave me his business card and told me to send him an email if I'm interested in attending a Ph.D. programm at his university. 

Now (4-5 months later): I will start my master's thesis in the summer and after talking to a lot of people (friends, parents, etc) I decided to contact him and ask about specifics. Turns out, I don't even know what to ask. (I havent sent the email yet btw).


In my eMail I start off with how we met (so he might remember me?) and then go on to say that he mentioned the possibility of the Ph.D. program at his university and gave me his business card. 
I then mention that I will presumably finish my studies Nov/Dec 2018.  (so he knows a possible timeframe)


I would like to ask him questions about the possible research fields, finance possibilities, etc - but our conversation was so short back then, I'm guessing I can't just ambush him like this. 

So what can I write between mentioning that I will finish my studies and writing 


"I am looking forward to hearing from you, Best Regards,xxx"


Also: 
What would be something a professor might want to know about me (should I include my CV already?), and what questions show that I am interested, without ambushing him completely? Should I write an "apology-sentence" that I am contacting him 4 months later and not in the following weeks?

Any suggestions are welcome! Thanks in advance!

PS: I am from Germany and currently also study at a German University.
I formulated my mail as a "letter of motivation" - Just in the same way you would write an application in Germany. You could start with something like 


  "Thank you for the nice discussion about the open PhD position in your
  research group at the XYZ conference in October 2017..."


Then, you should mention that you had a very close look to his/her research and that this perfectly fits your interests because of "this" and "that".

In any case I would already attach the CV with all certificates and required documents.