| You ask a question that there are as many answers as there are gardeners. What I would do is mow the weeds and rake to the side as a compost pile. Then I would gather as many leaves as you can and then either lay down cardboard or newspaper as a base. Top the base with all of the leaves and either grandular fertilizer or plain household sugar. Wet and allow to set until late winter. The sugar will help feed the organisims that break down the leaves. The wetting will keep leaves from flying away. Late winter I would remove the loose leaves to the compost and till. You probably will need to make several passes. Some gardeners never till but only dig enough to plant the veggies. A version of this is called lasanaga gardening. Check over in the Organic forum as there are many good ideas there. In my soil and weather I need to get as much material in the soil to lighten it and our rain washed the sheets of material out of the garden when I tried it. After you have built up the soil nutrients no till is a good idea. Since this is your first garden I would suggest doing a smaller space the first year or so unless you are going to do corn, melons, and squash. As a first year gardener even with lots of mulch caring for that large of an area and keeping all the veggies picked is a challenge. Do not do what one of my blog friends did and plant the whole package of cucumber seeds. Actually he planted 30+ hills of the things. A visit to the library and various seed sites is good to see what is out there. Like all gardeners you will find that you will purchase more seeds than you can plant so find a dark container to keep the leftovers in. Many will still grow after a couple of years if kept bug free in a cool dark place. Good Luck | 
