How to change Vibin contraceptive pills to Ginoring disc?

I am in the process of taking the first pack of Vibin tablets, but the gynecologist advised me to change them to Ginoring. Today is the time for a second placebo pill and I'm waiting for my period. My question is this: should I put the puck in when I get my period, or how do I choose all seven placebo pills? Thank you in advance for your reply