For scheduling projects and/or employees you can use the Scheduling module. This module can be activated under Settings (cogwheel top right) -> App Center -> Planning. This module is included in the Professional subscription.
Next you will see the 'Planning' tab under Projects. When you click on 'Employees' and unfold an employee using the arrow, you can draw a bar by holding down the left or right mouse button; see the green squares in the image below.
You work towards the green. You will then know that an employee is fully scheduled. In the image above you can also see that an employee is scheduled for 4 hours and has 4 hours left that day; then you will get an orange color.
If you start scheduling an employee and release the mouse, you will see the screen below:
In this screen you can specify various things, such as: the number of hours per day, the total number of hours, the period and the linked activity. Optionally you can add a description and indicate whether you want to repeat this on a weekly basis.
In this example the activity 'Consultation' is linked, you can see this in the image below: you can see immediately for how many % an employee is scheduled that week.
The handy thing is that you can bring the hours you have planned to realization.
This can be done by going to the Register screen. Next you can retrieve these hours by clicking 'Copy'. Note: this button is only visible in an empty week.
When you click on 'Schedule this week' all hours will be retrieved directly from the schedule, as you can see in the image below. The advantage of this is that the hours no longer need to be registered.
Each employee can then view his/her own planning. This can be done via My Profile > Planning: