This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
Enter them just like you would any employees. That is, in the menu, select assumptions/costs/personnel, then select the employees tab. However, unlike most employees, the labor for workers involved in manufacturing products for sales generally gets allocated to cost of goods sales. Therefore, press Advanced, and then change their Percent Expensed value to 0%.
Related Questions:
How do I add or change employees?
How do I add manufacturing overhead costs as COGS?
How do I handle outsourced manufacturing?