Using an air can (or just your lungs) blow into the adapter, plug in the card and DO NOT lock it into place. Just stick it in there and hope it stays....
When I got my phone I got it for the mp3 player. What I didn't know is that they expected me to buy a $30 connector cable. I tried to be the smart consumer and just bought a Micro SD card with an adapter. I plugged that bad boy into my computer only to find out that it was write protected. I figured out the painfully obvious way to unlock it.
Step 1: Adapter
The adapter is the size of a normal SD. Plug the micro into the bottom.