Some seeds, before they will germinate, need a cold period to break dormancy . Below are a few of the directions listed on the labels for some of those seeds:

Teucrium flavum - Lightly cover seeds and use 70F, germination in 1-2 weeks, if no germination in 4 weeks put in the refrigerator for three weeks than move back to 70F.

If the directions for your seeds read something like the above example, these seeds many times will germinate without the cold period and should be sown at the recommended temperatures first. If little or no germination, move the pots to a colder location (32-39F) for the recommended period. If sown into a pot - the pot can be put into a large plastic ziplock bag and sealed up and put in the back of a fridge or if its still cool, put outside. If put outside use a sheltered location outside, away from direct exposure to bright sunlight. It is important not to let the soil/seed medium dry out during the cooling period. Also the soil/medium should not be soaking wet - just damp. By putting the pots in a plastic bag you will keep the medium from drying up.

Alchemilla mollis - Sow at 65ºF for 3 weeks then move to Fridge for 3 weeks, return to 65ºF where germination will occur in two weeks. Light helps germination so surface sow.

If the directions are like the above example the seeds need a warm-moist period first and then a cold-moist period before they will germinate. You can do this a few different ways, sow in a pot as normal and seal up in plastic bag and leave at room temperature for the recommenced period then move the pot to the fridge or outside.
If the seeds are not two small, you can sow the seeds into a small plastic baggy or container with one tablespoon of moist (not soaking wet) seed medium/soil. Keep the container with the seeds and medium at room temps for the recommenced period then move to the fridge for the recommenced cooling period. This will save you room. Keep an eye on the seeds because sometimes they will begin to germinate while in the container or bag and at that time should be sown into a pot. Gently scatter the soil-seed mix over the soil in a pot and gently water down with a few hands full of water so that the seeds are in good contact with the soil in the pot. In the above example the seeds need light - so leave as is, otherwise sprinkle a thin layer of soil-medium over the top of the seeds and water some more.

Another way to sow the seeds that need a cold period is to sow them in pots or trays and place them in a sheltered location outside in the fall or winter. If the seeds need a warm-moist period first, they will need to be sown in late summer or early fall - or you can sow them inside in the winter and then move them outside after the warm period is done (Make sure that it will be cool enough outside, long enough to fulfill the seeds needs). One can also sow seeds in the fall and bring them inside again in late winter for early germination. This will give a few weeks of growth and larger plants when it is time to plant outside. If you have a cold window sill, it can be used for the cold period too - make sure that it stays below 42 degrees Fahrenheit for most of the day. If you use a cool window sill in the winter you may need to increase the cooling period by double, keep an eye for germinating seeds. ( Most seedlings of plants that need a cold-moist chilling period can handle cold temps as small plants, so do not move the pots until a good percent of the seeds have germinated). Keep soil/medium moist at all times and prevent drying by putting in a plastic bag.

For most seeds that need a cold-moist period, the cooling period does not need to be below freezing, with 34-39 degrees Fahrenheit giving the best results. But for most of the seeds in RANUNCULACEAE plus a few others, the cooling period needs to be colder, with 15-25 degrees Fahrenheit working well. The seeds include those plants in: Aconitum, Anemone, Caltha, Hepatica, Ranunculus, Trollius.

If you are not going to sow your seeds right away, they should be stored in a cool dry location, most seeds can be stored for a few years in the fridge. Seeds from tropical plants should be stored warmer 55-70 degrees Fahrenheit. Avoid exposing stored seeds to direct sun light and/or high humidity/water.