1- crops for direct seeding. The seed companies are mentioning carrots, beets, chard, lettuce, spinach, okra, corn, beans, peas, radishes, cucumbers, squash, pumpkins, watermelons. Most gardeners in the mainland states can probably do these. But in my location, I limit my direct seeding to beans, cowpeas, pigeon peas, peas, corn, squash, pumpkins, and watermelons. I do better starting the rest in trays in the mini greenhouses and transplanting the seedlings. Funny thing, but none of the companies mentioned herbs. Some of them are suited to direct seeding, though I start all mine in the mini greenhouses. Whether to opt for direct seeding or starting in trays depends upon one's environment, climate, experience, and personal preference. There isn't just one "right" method.
2- soil preparation. All the companies mentioned something about preparing the soil prior to seed sowing. Some went into more detail than others, but the general gist was to have no weeds, have the soil loosened, and make sure there was good soil contact (or coverage) for the seeds.
3- soil moisture. Every company instructed to water after sowing the seeds. Some said that the soil should be moist, but not soaking wet, before planting seeds. I like to have my soil nicely moist because when I water afterward, the water soaks in rather than running off. So I time my seed sowing after a nightly rain, or else I irrigate the ground the day before.
4- temperature of the soil and air. Not all the seed companies mentioned this. Some seeds require warm soil to germinate. At my location, most beans won't germinate during the winter because night temperatures are always in the 50's. And okra needs even warmer conditions for germination, so I plant it later in the spring when soil is consistently warmer.
5- thinning and spacing. Most seed companies were recommending close seeding, then thinning the seedlings to the desired spacing. The exceptions were beans, peas, and corn where the suggestion was to plant the seeds on the desired end spacing.
6- follow packet instructions. Not all seed companies print instructions in their packets. Those that do advised gardeners to read the packet and follow instructions. I wonder how many gardeners read those instructions?
7- label. Here's one suggestion that, in hindsight, I wish I had always adhered to : when finished sowing the seeds, label the row with the plant name and the date. These past couple years I've gotten much better at labeling things. But I'm guilty of not always getting the date on the label.
8- mulch. Some of the companies warned about applying mulch too soon. They suggested waiting until the seedlings were well developed. Yes, mulch can smother the very plants we are trying to grow.