First you are on your own. If you do this as all the mods on this forum you are responsible. It is fairly easy however to do. The pictures speak for themselves. 4 screws underneath the rubber feet pads. One screw has a warranty sticker on it. So yes, you can't do this without voiding your warranty. And no, I did not take pictures of the rubber feet and the screws. IF you need pictures of that, please do not do this mod. The top is held on with "clips" for lack of a better word. The top has the loops that seat in the plastic foot on the bottom of the case. So if you push on the sides of the case to take pressure off the top, you are adding pressure and the top won't pop off. I used one of those non-marring plastic tools to open laptops. Pushed the loops back that run along the back of the unit then could lift them off from the front clips. Once the top is off with the unit facing you the slot for the SDHC card is to the right. The card does in with the hook piece toward the left. Pops in easily. Button it back up. Fired back up. The router finds the card and mounts it. You can see it via the Asus SAMBA drive config tab to share it. If you are using Tomato than it'll be in the USB device tab. Tips: Format the card first. I forgot and had the file structure from my phone on it. No biggy but probably should have thought ahead a bit and cleaned it by reformatting it. Probably should put the biggest capacity card you can get your hands on. Mine is only 8gb as that is what I had laying around. I've seen 64 gb advertised but those are kinda pricey. However the 32gb cards are regularly 25 bucks. If you use the SDHC card for media serving and put songs on it, 8 gb does hold quite a few. 32 of course would hold the proverbial TON of songs and the memory card and the router could easily be a great music server. Good luck.