This is the method I use when needing to remove the engine cover / air filter housing. Once you compress the inlet tube using the accordian sections, the inlet tube will come off easily on each side. Then the cover is easier to remove since these inlets are out of the way.

Worth noting here that precaution should be taken when re-installing the engine cover. First, make sure the rubber seal on the engine cover at the rear is seated properly in its location. Then apply silicone lubricant lightly to the seal (I usually spray a paper towel and then wipe the seal with it). Seal will slip over the throttle body connection much easier having done this. Make sure you get a good & proper seal at the back where the engine cover mates up with the throttle body inlet.

The first time I removed my engine cover to install a pair of K&N filter elements, I found this large rubber seal damaged from an earlier installation that was done poorly. Had to apply some black RTV sealant to the damaged seal to get it back to near OEM looks. (Note: I've since found this seal at OEM Discounts Parts for $5.)