7 Month-Old Requires Far Too Much Of My Time, What Should I do?

I run a small day care operation in my home. I have a 7-Month old that is here 2.5 days per week. The baby cries whenever it is put down. I cannot put the baby in the exersaucer or bouncer set or high chair or on the floor to play with toys or the baby cries. I am having a hard time with this as it is really interfering with caring for the other children that I care for. The baby needs to be held constantly or crying and screaming happens. I cannot do very many activities with the children the days that the baby is here as I do not have my hands free to help them with their art activities or to do finger plays with them or anything else that requires me to have my hands free. I have tried a front carrier and the baby scream when placed in it! So I am looking for suggestions. What can I do about this to make my days go better with this child?