Posted: 12/12/2014 at 08:18
Hi Andy - Merry Christmas to you too
At this time of year you can give it an established lawn a good spiking all over with an aerator or garden fork - this will get some air down into the soil and also help drainage. Other than that I'd leave it alone in the wet soggy weather and try to keep off it when frosty or when there's snow on it.
In the early spring you can use an all in one lawn feed which also contains weed and moss killer - it's a good idea to hire/borrow a spreader for this as it's important not to over apply it. This will kill off lawn weeds and moss and then you can rake them out. The lawn will look a bit grim for a while but the lawn feed will soon perk the grass up and it will spread and take over the bare patches. If there are any thin areas left by September a sprinkling of lawn seed will soon remedy that and then you'll be well on the way to having a lawn to be proud of.