From a complete Novice last year, I did pretty much what willni suggests above on my Grandparents garden, it had been left for ages, so I dug it all out and started a fresh ( I was on some sort of health mission haha )
I sectioned it off, graveled most of the front, put in a new fence in the back, but kept a manageable piece that took really quickly from seed and fertilizer, and loads of water; used a digital timer from Screwfix, about £20 highly recommend... so plenty of sunshine, water and feed, don't cut it, good luck :)
and of course you need to build a bird house from scrap wood :)
Waffle waffle waffle, haha
It has a strange sense of satisfaction watching it come together :) Good luck mate :)