Depending on where you are & where you want to CTB then you might want to:
1) make sure your bills are settled and cancel requests have been submitted for credit cards and subscription based services like Netflix, etc.
2) utilities that might need disconnecting - make sure to know if they need someone present when they turn it off too
3) Rent or lease
4) i'd empty my bank accounts and give away the excess amount.
5) give away clothes, books, etc, basically get rid of material stuff. Sell what I could, donate/give away the rest.
6) For some people it's important to leave a note. my CTB plan doesnt have this requirement but hey, just in case you need it.
7) Funeral/Cremation arrangements
8) Social media account/email accounts - if they have a delete account feature, use it.
9) Factory reset your other devices (tablet, computer, etc)