Coleus may be a little slow to get started but just wait for it. Watching these little sprouts slowly grow into little, wildly-colored mounds and then lushly filling out whatever beds or containers you put them in will be a true delight.
If it’s warm outside, direct seed and keep moist until sprouted, then water whenever they seem dry. Once plants get tall, they’ll droop when dehydrated and then quickly recover once watered. If it’s still cold outside, start inside since it takes a while to get them going and they don’t germinate in anything less than 70º. Use a heat mat and grow lights. Press a few seeds into the soil surface of each cell or pot. When 1" tall, thin to just the cutest one. Set outside once they are at least 3” tall and the days are consistently warm. Space 8-12” apart. Or just grow them inside as houseplants! Once you’ve got seedlings, it’s very easy to separate out the ones you want into separate pots.