One and another thing... there are lots of tutorials around that refer generically to the 2B & 3B operation.
Prob'ly not an issue, but all the earlier Pi models 'clicked' the microSD card into place- click & push in again to release the card.
The 3B just slides the card into place, and is not pressed again to remove it.
Also, the card does a little housekeeping after the software is shut down. The indicator lights work differently than the 2B, wait a little bit before pulling the AC adapter to avoid corrupting the card.
But wait there's more! The Pi can now clone it's own card, so when it is nicely personalized that USB card adapter can come in handy!