Posted: 05/05/2014 at 18:07
Two words Daniel, "Oh Dear" I do wish I could say do A-B-C and it would be fine, no such luck.
Question, is it a new build? If so get them to relay it, if not is money restricted as it could be a long and costly job.
The obvious way is to rip it up and start again, then I would ask do you need all that area as lawn. You could plan a new garden altogether, three different sections with borders properly laid lawn and a play or patio area all with trellis dividers, think three rooms all for differing purposes. It would need you to sit down and watch where the sun rises sets and which area would be best suited for a warm seating area.
All that depends on your likes needs and cash flow although split it could be developed in sections as time and cash allows. It will not be a short or easy project although if you treat it as a project in sections then it will be easier than trying to sort out a battlefield. Talk about it draw up some plans and look at the design sections on the internet, ideas will come.
Best of luck, Frank.