You can assign user to a task in two ways: using a bench, or using task's details window. Since we've shown already how to assign user to task using bench, we will show the other way only.
Assign user using task's details window.
First, you need to open the task details window by left clicking on the task you want to assign the user on. A window should appear similar to this.
Task Details window.
Now, to start assigning a user, we need to click this icon.
Users icon.
New window should appear where we can assign user to task.
Now, to assign someone to task, we just simply need to choose him from dropdown button and click "Przypisz".