At the right you see all you need to grow alfalfa sprouts:
In the picture I've used a metal ring to secure a patch from the lady's hose over the jar's mouth, but you could also use a rubber band or piece of string. You can use other kinds of woven fabric or screen. What's important is that air and water can pass through it, but the seeds can't. Note the small quantity of seeds in the jar. Two tablespoons per quart jar is about right.
Soak the seeds overnight. Fill the jar at least a quarter full with room-temperature water and just let the jar sit.
Pour out the water and let the seeds sit. You want to seeds to be wet and to have access to air. Therefore, don't let the seeds gather in clumps at the jar's bottom. In fact, take advantage of the fact that the wet seeds want to cling to the jar's inside surface. Roll the jar around, causing as many seeds to stick to the surface as possible, then lay the jar on its side. If the surrounding air is cooler than 70° - 80°, the seeds will grow slower than if they had more heat, but that's OK. Warmer temperatures encourage disease organisms. If you prefer growing them under warmer conditions, then rinse at least twice a day or more. If you are not rinsing enough, you'll smell a funky odor in the jar and need to rinse more often. At this stage it doesn't matter whether your sprouts have light or not.
Rinse the seeds twice a day with cool water. Just run the water into the jar, swirl the seeds around, then pour out the water through the top filter and repeat Step 2. The idea is to rid the seeds of disease organisms and toxins that accumulate in the moist conditions inside the jar. The picture at the right shows sprouting alfalfa seeds stuck to the side of a jar. The picture below shows the same jar at the top of the page. You can see that the small amount of seeds we began with now fill the jar with half-grown sprouts. At this point you might pour half the sprouts into another jar and continue the process. Eventually both jars probably will be full of sprouts!
When the sprouts are big enough -- usually on the fifth or sixth day and looking like those at the right -- spread them out and let the sun shine on them a few minutes -- maybe 15 minutes, more if you want. This important step activates enzymes and makes the sprouts prettier by making their leaves greener. The brown seed-coats will have come off most beans. If you want, you can remove most of the coats by submerging the sprouts in water, then filtering out the coats, which tend to float to the top. Removing the coats won't change the taste or nutrition.
(You can refrigerate your sprouts once they've drained well.)
PS: Once you've mastered alfalfa sprouts, try sprouting radish seeds (avoid garden seeds that might be treated with pesticides) whose sprouts are larger, more colorful and with a radish or cress-like taste. Below you see radish sprouts with sliced tomato in a cornbread sandwich, an outside snack for a morning spent painting a house, and it was soooooo good!