Once the bed has been prepared and raked down smoothly, it is ready for planting. If you plan to use seeds, be sure you have fresh viable supplies that will germinate well. Some flowering annuals can be sown in late fall or as early in spring as you can work the soil. Examples are calendula, cornflower, larkspur, portulaca, and spiderflower. Seeds of certain robust and rather large-seeded annuals germinate reliably when planted directly in the ground.
Good examples are balsam, cockscomb, cosmos, dahlia, four-o'clock, marigold, nasturtium, and zinnia.
Wait, however, until the soil is warm and danger of frost is largely past. Many other annuals are either smallseeded or rather touchy in their germination requirements. Unless you have proper facilities for starting them indoors, or in a hotbed or greenhouse, it is probably best to buy started plants. These also will give you earlier blooms than from seed. If you start your own plants indoors, don't sow the seed more than 4 to 8 weeks before the average date of the last killing frost.