1. Plot out your garden area. Decide on what you want to plant and how much room you will need to grow those plants. Also, the amount of sunlight is very important in picking out the proper placement of your garden. You will want an area that gets direct sunlight most for the day. Something else to take into account is the drainage of the land. You will not want your garden in a depressed area of land because water will tend to flood those areas and won't drain properly. I prefer using a slightly sloped piece of land or a flat piece of land that retains and drains water properly. Once you have chosen the location and size of you garden you will want to mark the boundaries of the garden with stakes or flags.
2. Next is the part of the job that will likely take the most time, preparing the soil. Preparing the soil means two things to me:
A. Cutting and removing the sod. You have several options when deciding how you want to get rid of the grass and get down to the soil. If you have a very large garden you may want to hire somebody or rent the equipment (bobcat) to tear up the grass. If you own a rototiller (you can rent one), you can use this to remove the sod. There are two main types of tillers, front tine or rear tine. Rear tine tillers have the blades in the back of the machine and typically are a bit easier to use due to the fact that you (as the operator) get more weight / leverage over top the blades. Front tine tillers have the blades in the front and can be a bit harder to use on hard sod or compacted soil since there is not as much weight / leverage over top the blades to make them bite in as well as a rear tine tiller. If you have a very small garden area then you may also choose to use a shovel to tear up the sod. Personally, my brother and I used a tiller to tear up a rather large patch of land for our garden. We would run the tiller over the grass to break it up then rake the grass clumps into one large pile in the corner of our garden, which eventually decomposed to plain dirt. We had to run the tiller over the garden area several times and rake clumps of grass each time before we had a workable dirt area. This can be a back breaking task so make sure to take your time and rest sometimes.
B. Getting the soil ready to plant in. Plants will produce their best when they have a healthy, somewhat loose, soil to grow in. This means that you want a nutrient rich soil that retains just the right amount of moisture. You can take soil samples into many garden centers to get a test done. A soil test will tell you what you need to add or balance out in your soil. The three key nutrients in soil that you will need to worry about are: nitrogen, phosphorus and potassium. Any and all of these nutrients can easily be added using organic or non-organic methods. Ask your garden center what you should use for your soil. I was fortunate with my garden because the land we put our garden on used to be old farm land and was great soil. We simply tilled the soil several times to loosen it up before we created rows.
3. Next you will want to create your rows and plant your seeds or seedlings. To do this, follow the directions for row and seed spacing on the back of your seed packages (you can also find all your planting information at the website listed in the resource box below). Many plants require 24 "to 36" between rows. Make sure to leave adequate room between your rows to allow you to walk and / or till between them. I like to mark where my rows will be, by driving stakes into the ground on each end of the row and tying twine between the stakes (I use a tape measure to mark the distance between my stakes).