Two other possib.

dressing up
dusting down and doing up
putting on the warpaint
spring cleaning

.....

get in trim
make shipshape
give a makeover
renovate
spruce up
neaten

Another thought: give your boat a makeover that is kind to the sea too

Either just like that, or "Getting ship-shape and Bristol fashion".

Not obvious to non-natives of course (but then I rather doubt "sprucing up" is either), and a tad removed from the original, but "ship-shape and Briss'l fashion" is very nautical.

"Ship-shape and Bristol fashion
Meaning
In first-class order.
Origin
In May 2005 there was a brief flurry in English newspapers concerning the origin of the term nitty-gritty. A company that had recently presented an 'equality and diversity' course in Bristol had suggested that this term was a reference to an ethnic slur and should no longer be used. Those English journalists with a seek and destroy mission against political correctness rubbed their hands when, much to their satisfaction, it turned out that the claim had no substance.
What wasn't picked up by many at the time was an additional claim that 'ship-shape and Bristol fashion' was also a derogatory description of black people who were ready for sale as slaves. This is also unsupported by any evidence. The phrase has a perfectly sound derivation which is nothing to do with race.
'Ship-shape and Bristol fashion' isn't widely used outside the UK and even there less so than in earlier times, so a little background may be in order.
Bristol has been an important English seaport for more than a thousand years. The city is actually several miles from the sea and stands on the estuary of the River Avon. Bristol's habour has one of the most variable tidal flows anywhere in the world and the water level can vary by more than 30 feet between tides. Ships that were moored there were beached at each low tide. Consequently they had to be of sturdy construction and the goods in their holds needed to be securely stowed. The problem was resolved in 1803 with the construction of the Floating Harbour. There's no absolute proof that the term 'Bristol fashion' originates with that geography but the circumstantial evidence seems very strongly in favour of it.
Just as an aside, Bristol has another linguistic claim to fame. In earlier days the town was called Bristowe (or Brigstow). A quirk of the local spoken dialect is to add els to the end of words, hence Bristowe became Bristol. Another nice example of this is the name for the laminate sheeting used on worktops. You might call this Formica; in Bristol it is Formical.
"http://www.phrases.org.uk/meanings/ship-shape and Bristol fa...

My mother's family is from Bristol, and I remember uncles telling me about their travels to Canadal and South Africal in the 1920-30s, taking pictures with their cameral, and an aunt telling me how much she enjoyed a good operal. Don't recall any lapses from my mother though!


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Note added at 1 hr (2009-04-16 09:15:19 GMT)
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You could even claim that any sexual connotation in "se (re)faire une beauté" is reflected through "a pair of Bristols", rhyming slang for "Bristol City(ies)" = "titties". But then I'm a bloke.

It's kind of mix of what has been submitted earlier.

Another suggestion- didnt see it mentioned yet.

The quotes aren't showing up in the preview...but it should read:

spiffing up your boat...while keeping the waters "green"

Hi there Miranda !
I'm about to go out for an hour or twon but here's a few ideas - for what they are worth - to get things started :

doing up the boat

smartening up the boat

freshening up the boat

giving the boat a new look

restoring the boat's good looks


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Note added at 1 day50 mins (2009-04-17 08:37:24 GMT) Post-grading
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Thank you Miranda, but I agree entirely with your choice. Wish I'd thought of it myself ...