Mind itself, buddha nature, is empty, clear, unceasing awareness. When you experience that mind is empty, devoid of intrinsic being, you are taking refuge in buddha.
Dharma is clarity
To take refuge in the Dharma is to experience the clarity of awareness itself, a clarity that doesn't come from anywhere, doesn't go anywhere, and is not located anywhere.
Sangha is unrestricted experience
When experience arises and subsides freely, without restriction, with no effort or control on your part, you are taking refuge in the Sangha.