Are you buying Brineshrimp eggs or actual adult shrimp?
If you buy the eggs they come in a small phial and you put a small amount of the eggs (1/2 level teaspoon) into a 1-2 litre container of saltwater. I use seawater out of the fish tank. Have an airstone bubbling away in the water and keep it warm. I place the container on top of the fish tank. The warmth from the tank makes the eggs hatch sooner. Get a plant mister and have some freshwater in it. Several times throughout the day spray some freshwater around the edge of the container with the eggs in. The air bubbles cause the eggs to stick to the side and they won't hatch if they aren't kept wet. Spraying water on them washes them back into the water where they will hatch.
After 24-48 hours the brown eggs will have hatched (it depends on temperature as to how long they actually hatch, the warmer the water the faster they hatch) and there will be tiny orange things moving around the container. Take the airstone out and put the container near a light. The nauplii (baby shrimp) will collect near the light and you can use an eye dropper or syringe to suck them out. Try not to suck up the eggs at the same time as the fish won't eat them and if baby fish do eat the eggs it can cause problems. When you have taken some shrimp out replace the airstone. The nauplii will survive in this container for a couple of days.
If you put the nauplii into another container of seawater and feed them on green water then after about 3-4 weeks they will be mature. They are most nutritious when newly hatched as they still have a yolk sac.
If you want to keep the eggs for a while then put them in an airtight container and keep them in the fridge.
/www.skepticalaquarist.com/docs/feeding/brinesh.shtml
