The answer is in your owner's manual. Just go to the parts dept of your dealer or to an auto parts store and get the filter. Next, empty out the gloove box. DIsconnect the damper (it is on the right side of the glove box that prevents the glove box from falling open too fast) Grip the top front of the glove box with your left hand and the top rear with your right hand and then push your left hand toward you and your right hand toward the front of the car, like you are trying to make the top of the glove box wider. While you are doing this, pull the glove box toward you so that the glove box is hanging down, (if it was full, it would have spilled the contents on the floor mat). Then the cabin air filter is toward the front of the car, just squeeze the two tabs on the left and right side and pull straight out towards you. You have removed the cover for the cabin air filter. Now, slide the filter out and put the new one in. Reassemble in the opposite that you disassembled.
Again, see your owner's manual, it tells you how to do it and saves tons of $$. This only takes 5 minutes or less.