I suggest you read up about partitioning your SD Card with an Android Recovery system. Google is your friend, Looking it up and reading it on you're own will do more justice than me explaining it to you. You'll learn better that way.
As for using Link2SD, It's rather simple. Since you haven't partitioned your SD Card yet, you can't link anything. All you can do is "Move" them to the SD Card. You can do this by following these instructions:
1. Long-Click on App you want to move (A menu will come up)
2. Select "Move to SD card"
Walla, the .APK is now on your SD Card instead of using up internal space. This will free a lot of space, not as much as "Linking" the App but enough to make a noticeable difference. If you're really looking to free your internal space, Do as I originally stated. Look into partitioning your SD Card and add an sdext partition.
** note **
Certain apps don't place nice after being moved to the SD Card. It's trial and error, if the APP stops working after moving to sd. Move it back to internal.