Mossy lawn

Last year I offered to mow the lawn (about 50 square metres) of an elderly friend. However, I found myself mowing moss rather than grass. I would like to change this moss lawn into a grass one, but my friend does not want to have to put up with going through a stage of having a lawn of blackened killed moss. Nor does he want to remove the surface and start from scratch. Is there a way of making the change gradually while still maintaining the nice green appearance the moss currently gives? Cost would have to be minimal. 

I don't think there's an easy answer for you, unfortunately.  If there's mostly moss on the lawn you're mowing, it's probably there because the grass won't grow well under those particular prevailing conditions.  Is it very shaded?  is it at the bottom of sloping ground?  both of these situations can mean that moss is likely to flourish at the expense of grass - as I know only too well ref my own garden.  Even if you were to re-turf, moss would probably win in the end.

I've given up trying now - but at least that part of the "lawn" is green!

When we moved here the neglected lawn was mainly moss, partly because of the high ivy covered fences and partly because of the shade of the big trees and the fact that fallen leaves hadn't been raked up for years.

The first thing we did was to improve the light by having the crowns of the trees expertly lifted and thinned.  The ivy covered fences fell down and have been replaced by fences with honeysuckle, roses and clematis climbing up them.

Now, 18 months later the lawn is looking much better simply by regular vigorous raking and spiking and regular mowing with the hover mower on a high setting.  The only fertiliser I've used is a single top dressing of  sea weed fertiliser - I've not used any moss killer as we have amphibian/reptile visitors 

You can give it a fine rake, that will take out some of the moss but depending on how long its been there the grass may have died underneath. Like Dovefromabove says, airate it with a fork (garden not kitchen) the moss doesnt like that, a sprinkling of sharp sand will help with drainage. 

I found these videos very helpfull 

http://www.gardenersworld.com/how-to/projects/lawn-care/

Get some Lawn Sand from Wilko's, that will sort it out. Its fantastic stuff.

Thanks to all who answered my query. Shade is not a problem, but the need to aerate struck a chord. I have opted for aerating with a fork and a bit of fairly gentle scarifying as a starting measure, and we will see how it goes.

moss is a big problem at the moment because of last year's wet summer. Aeration and raking will help a lot, but what we need is a dryer summer and some sun!

Thanks for the tip about lawn sand from Wilko's, Gray. It really appeals to my economical nature.

probably cheaper to buy sharp sand from homebase/ B&Q it's about 2 quid or less for a 20kg bag!! (This is assuming that wilko lawn sand is only sharp sand)