Floating images to the left

I would like to have my blog image - that main image - float to the left - and on previous installations I'm pretty sure that the float was configured - but I can't figure out how to get this to work.

I also had a much more complete editor - and wonder if there is some kind of add on editor I should activate - I've tried with JCE and with Rok - but neither are giving me as much control as I recall having on the past...

I've attached a screenshot of another blog I write on and here the image floats left.

How do I achieve the same thing on my new site?

http://europeanprinter.com/index.php/european-printer-blog/entry/greecing-the-wheels-of-european-printing