The battery comes half charged from the factory, so you can use it straight away.

I used mine straight away without charging at all, until the factory charge was finished and it died. Then I plugged in the charger and charged it fully, switched on while continuing to use it from time to time.

That's what I continue to do, most of the time: Use it until it dies, then charge it fully. Occasionally I charge it when it's not completely dead, just for variety :-)

I'm very pleased with the battery life I've had, from the beginning, so at least there doesn't seem to be anything harmful with that approach.