Growing seeds indoors provides the home gardener with a lot of pleasure over the winter months. It is necessary to have a good source of light (either the the direct sun or a grow light) and for germinating seeds, a source of bottom heat.
Select a container to grow seeds that has good drainage and some depth. (I have used milk or juice litre or 2 litre containers with holes punched in the bottom, and more recently 4” plastic pots).
Wash these well and disinfect them. Fill these to within 1/4’” of the top with soiless mix, tamp down the soil and moisten the pot.
Sow seedlings in the mix, being careful not to crowd them, and paying attention to the package instructions (some seeds need light to germinate while others can be planted below the soil level).
Cover the container with plastic and place on a tray where it will receive constant warmth (a heating cable under a growing tray can provide this warmth Other alternatives are the top of the refrigerator.)
Leave the seeds until you notice that they are starting to germinate. As soon as some germinate move the container to a location where it will receive strong light (eg. close under lights, or a sunny window). The rest of the seeds should germinate over time, but it is important to get any seedlings into strong light so that they can grow strong stems.
Once seeds have germinated, they can moved from the ground heating source. As long as seeds get sufficient light they will thrive even under cooler temperatures.