I have seen a transfer window but I don't know what to do. The transfer window gives a period of 8 hours and money spent that day.
How do I request transfer?
Go to My Pro (second option across top of the screen) then select My Actions. You will see the following options:
You should be able to do this during the final transfer day (which is when you see the countdown and total money spent).
You probably won't have the Request Transfer option if you are already out on loan. I believe you need to return to your parent club before you can request such a transfer.