You'll need a T25 Torx head screw driver and maybe a standard (either flat or philips, I forget) for the hose connection, can't remember if thats T25 or not.
There's screws on the top of the box, the front ones secure the lid and the back ones secure the box itself. Remove the hose connection and undo the T25s on the rear of the box then pull the box directly up and out of the engine bay. From memory that's it, its very straight forward and looking at the box you should see what you need to do.
You could google instructions for the Alta or Forge air filter if you'd rather have pics.