As an Admin you can delegate one managers people to another manager while that manager will not be there.
The first thing that you want to do is login and search for the employee who needs to be delegated. You do this by going to the Team > My Team > Employee Information.
Then search for the employee who needs to be delegated and choose their Employee Information button.
On the employee's Main Tab you will use their Jump menu to find Workflow Delegation.
Now under workflow delegation in the right hand corner hit + Add.
This will bring up the workflow delegation box where you will do the delegating.
Delegate to: Choose the manager that you wish to delegate to.
Workflow Type: If only one specific type is needed to be delegated then delegate that. Otherwise choose All Workflows
Date From: First Day of Delegation
Date To: Last Day of Delegation
Workflow Group: Name of manager who is delegating
Then click Add
You have now delegated to the employee and all to do items will go to the other employee's bell.