Unlike the Q5, the Z30 back cover can be completely removed although it can be a little tricky. Hold the BlackBerry so that you can insert your fingernail into the gap in the bottom of the case. Now gently prise the back of the case off while you slide your finger to the side. Once you can pull one part of the back panel off - the rest should be easy.
The SD Card and SIM card will be clearly labelled with clear icons. Make sure that you align your cards the same way so that the notch appears in the same place and slide the card into the gap in the side of the Z30.
Once it's in, you should be able to feel it snap into place. When you want to remove the card - push against it and it should pop out. Now just pull it out with your fingers.
Check out the video to see it in action.