Priority considerations, before you even book that ferry, is to ensure that you have your " pet passport" ,for without this there will be nothing stopping you taking your dog on holiday with you, but you will find that you will be leaving your best friend in quaratine for 6 months, when you come home.
The primary requirement for the passport is that your pet has had a rabies injection and a subsequent blood test, to ensure that it has produced the necessary antibodies. This is not a quick process, check with your vet with regard to the timescales.
Your pet will also have to be microchipped before the rabies injections
Armed with your pet passport all you need to do is now book your ferry or the tunnel, telling them that you have a pet.
There will be a small charge and they have to stay in your unit, so turn off your alarm or you will not be very popular.
Now it is time to enjoy your holiday. On our second trip with our dog, we did the chateaux a velo cycle routes and rather than buy a very expensive purpose built dog carrier, we went to Halfords and bought a kiddies carrier, albeit he proved to be a very hairy toddler. A quick spin around the cycle route, on the Bay of the Somme at Le Crotoy, as a taster and we were away.
Always make sure dog has plenty to drink
Before you come home, you must arrange a vet in France to provide protection against tapeworm.
This process is much more flexible now. Your visit must not be less than 24 hours before you embark or more than 120 hours, i.e between 1 and 5 days, get it wrong and you will not sail .
I have always found that the vets are fully familiar with the scheme but check that they do complete the pet passport correctly.
To obtain a vet there are services that will do this for you but they will charge you and basically there is no need; just use the link below for "French Yellow Pages", google transalte it. Type in veterinaire in the first box and the name of the town in the second one and then click on "trouver".Try and find one with e mail to avoid a telephone call. Do not worry I have always found that someone will speak English.
Now that you effectively have 5 days to organise your appointment , you could always ask your campsite to book this for you whilst you are abroad.