During the day: Front and rear blinking

At night: Front: steady on the handlebars and strong steady on my helmet*
Rear: blinking

*As a side note, I love my helmet light when it's dark for a number of reasons.
1. I can point it to what I want to see that might not be immediately in front of me.
2. I can point it into a turn or immediately before a turn to see the terrain of the road or path I'm about to take.
3. It is an extra light in case I want to see something farther ahead of what my handlebar light is focusing on
4. I can use it to alert a driver of my presence in an intersection. I've really seen this work very effectively. I usually shine it at the driver coming into the intersection who wants to make that right on red. I will shake my head (and therefore my light) back and to bring their attention to me. Then after two or three passes, I make sure I remove the shining light from their head to prevent blinding them. I also use this effectively when I'm making a left turn and someone is in the oncoming right lane trying to make a right on red while I'm making my left turn. As I pass, I friendly wave to the driver for giving me the right of way (even when I should have had it in the first place).