You will want to suspend a heat lamp over the brooder and you should also make sure there are two means of securing the light to keep it from falling. Measure the temperature at the chicks and start with 95 degrees and then reduce heat by 5 degrees each week. Another indicator is to watch the chicks. If they are huddled tightly they are trying to stay warm. I have found you will want to avoid boxes with corners as that can lead to piling of the birds in a corner and often crushing a chick to death. One of the best things I ever used for a brooder is a material called thermoply. It's a cellulose board material that comes in 4x8' sheets and used as panning in HVAC systems. Home Depot sells it and it is quite cheap. Cut it into two 2'x8' pieces and join the ends together to for a circle. Place newspaper on the floor and then set ring on it. After a couple of days I would place fresh newspaper next to it, and then with another persons help we would lift the ring slightly and "walk" the chicks onto a clean floor. Roll up the fouled newsprint and discard. After a couple of days repeat process. Keeps the birds clean and healthy, keeps the smell to a minimum, and gives the birds plenty of room and allows them to move about to find the environment they feel most comfortable at. When the birds are about 3 weeks old you will want to cover it with a cheap light weight plastic mesh to keep them from flying out.
Hope this helps and enjoy your birds.
