Drainage holes need to be drilled in the bottom of solid containers. Light Inadequate light is the most restricting factor in seed starting and will lead to weak, spindly, stretched seedlings. Inexpensive fluorescent shop lights should provide all the light you will need. Hang these from an adjustable chain. This may vary depending on the seed you are planting.
Some seeds germinate better at lower temperatures.
Bottom heat can be provided with heat mats or cables designed for this purpose. Do not a fluctuating heat source like heat vents and keep seeds away from cold drafts. After seeds are watered in, cover with a plastic dome or saran wrap to increase humidity. As long as condensation is visible inside the cover, do not water. When condensation starts to dry up, water lightly.