We have rotations of 3 to 4 stations a day. During one of their stations they meet with us which may leave a student alone in their center but this works out fine. In Kindergarten I set a timer for 10 minutes at the beginning of the year and slowly work the stamina per station to 15 minutes. In First grade Katie sets a timer for 20 minutes per rotation. During each rotation we meet with a guided reading group while students work in their stations. In Kindergarten I start the year with 2 rotations per day and then work our stamina up to 4. When the students hear the timer go off they clean up and wait for the bell to change to their next center. Each week in Kindergarten I would mix up the centers so students were not missing the same centers when meeting with me for guided reading. Here's a picture of our center boards at the end of last year.
I got the station cards at School Box and laminated them. I bought two sets and and put the other icon on the box to go with that center. Katie made her own cards.
For noise control and staying on task check out The Lesson Plan Diva's Center Patrol Idea.
If you have any questions feel free to ask!