You can use GCash to transfer to a BDO Account. Just open your GCash and go to 'Transfer' and select 'BDO Unibank'.
If you're having problems, you can also transfer using Instapay:
Click here to learn how to transfer to BDO using instapay.
Make sure to take a screenshot of your successful online transfer, or a photo of your over-the counter deposit slip.