Young children, especially those who have never been to school before, are almost always nervous and even a bit afraid when they first come to class. As their first teacher, your job is to make them more at ease with their new environment. Give every child a name tag so that you can quickly begin calling them by name; this will also make them more comfortable. At the beginning of class, have quiet music playing so the children will feel more relaxed.
Have a supply of tissues handy for any crying or nose blowing. Also, have a few stuffed animals and puppets handy to calm them when the children get upset. Set up an area in the room where they can place backpacks and other personal items. This will keep the room from becoming disorganized. Place a name tag on each desk for the first week until everyone knows where they are supposed to sit.
It is important to work based on a schedule since children like consistency. This means you should have snacks, nap times (if any) and lunch at the same time every day. Start each class by taking roll and making sure everyone has settled into their seats. Make sure that if you write assignments or other information on the board, you always do it in the same area of the board. Have a set area on your desk for sheets you want to give students and always place them on the same part of your desk. By the same token, if you want students to place an assignment on the desk, always have them put it in the same spot.
It is important to maintain control of the classroom or nothing useful will get done. For this reason, you need to have rules and consequences if the rules are not followed. Explain the rules, such as no shouting, fighting or leaving class without permission, on the first day of class. Reinforce them as needed. For discipline, set up a simple mechanism that lets the child know if he has misbehaved. For example, draw a smiley face on one section of the board and a sad face next to it. Place each child's name on a sticky note and put it in the smiley area. When a child misbehaves, move it to the sad area. If he behaves for the rest of the day, move it back to the smiley area.