You can transfer a Skype for Business call to another person or number. For example, if you need someone else to handle the call, you can direct transfer to them. Or if you need to leave your office, but want to continue your conversation, you can transfer the call to your cell phone.
1.Click on the pop-up to accept the call.
2. When you need to direct transfer , click on Call Control and select Transfer
3. Search for the person you need to transfer and click transfer to finish.
Refer to below video for visual instruction