Lay out your beds or rows so that you can easily mulch or mow between them. If you have time before you plant, bring in a load of blended compost and soil from a garden center, and spread it at least a couple of inches deep over the planting areas.
Now, buy a good weeding hoe, such as a stirrup or diamond hoe. Use it early and often, cultivating shallowly to kill any sprouted weeds without stirring up the remaining buried weed seeds. Once your soil is warm and crops are up, mulch as much of the garden as possible with straw or grass clippings. To smother weeds and build the soil in all unplanted areas, plant cover crops, such as buckwheat (in summer) and rye (in fall).