Hi GF, once overtaking (if you feel the need to) you'll feel right at home i'm sure, because then you are back on the side of the road to which you are accustomed... Just remember to move back over to the left if you see any approaching traffic though!
The first time i did any continental driving i as worried about the dreaded overtaking manouevre too... I need'nt have worried though... The French are just so much better regarding the whole overtaking thing, that any problems i envisaged never materialised
Be warned though! British drivers really are pretty awful! You really have to watch out for them... If they DO indicate at all, bank on the indication being wrong, the rest of the time they'll simply ASSUME you know where they are going to swerve to next. Be prepared to experience shocking lane discipline,selfishness, and "oneupmanship" simply for the sake of it. Forget trying to keep a reasonable distance between yourself and the car in front... If anybody behind you see's "a gap" they will overtake you simply to fill that "gap" (as they see it).
Just class driving over here as being a defensive excercise, i wouldn't advise being offensive in driving style, because the "next man" WILL hit your car rather than (In his eyes) "chicken out". Be prepared to stop at each and every traffic island/roundabout you encounter, even if you have priority, expect a car to come from nowhere as brits have an affinity of only indicating OFF a roundabout (what's the point?) NOT on to it...
I'll await the stick for my post from other brits
Most are as patriotic as they are bad at driving!

WAIT FOR IT!