First head to your profile page. You can do this clicking on your name at the top of the screen (your name will show where it says "Romilda Vane" below).
Once on your profile page, click on the Declarations tab (second along).
Here you can confirm that you've read Keeping Children Safe in Education using the Confirm button. There is also a link to the document itself.
* Note - the link provided is always to the most up-to-date version of KCSiE
Once confirmed, the date of the confirmation is recorded on the system, and will appear in the Confirmations report available on the Downloads tab/