The air filter housing is a large plastic box dead in the middle of the engine bay.

The housing cover is attached with 6 latches (A) that need to be undone. A quick glance around the box and you'll find them, but I've labeled them in the picture below anyway.

You should be able to undo each latch easily.

Once the latches are removed simply pull up on the housing cover to remove it.

The lid will become completely detached from the rest of the housing - you can simply put it aside.

Now we see the filter. Pull on the filter to separate it from the rubber hose that it's connected to. You may need to turn and twist the filter to free it from the hose, but it shouldn't give you much trouble.

With the filter removed you can see all the debris that has wound up in the housing. Take a second to clear out the debris.

Your new filter will be oriented like in the picture below. Note the plastic peg (A) on the filter - this will fit into hole (B) when the filter is attached.

Push the filter into the hose, making sure that the plastic groove (A) lines up with the rubber nub (B). Once the nub is sitting into the groove the filter should be aligned correctly, and you can seat the plastic peg into the hole (as shown in the step above).

Now you simply need to latch the housing lid back on.