Make yourself a handy credit-card sized SD card holder and keep up to three SD cards in your wallet, ready for those storage emergencies.

So here's how it started - I went a little crazy one afternoon last week and bought myself a lovely new IXUS 70. So tiny and perfect.... imagine my joy! But then frustration set in - the SD cards came in big clunky plastic cases - four of them together are almost as bulky as the camera itself - what I really needed was a nice slim card holder to slot into my wallet.

sarCastro's Instructable was my first port of call. It's a good shot at the problem, but I needed something a little more sturdy and a little less prone to accidents with my clumsy big man-hands. So on with the inventor's hat...

Step 1: Attempt #1 - Cutting and Gluing Like There's No Tomorrow...

My first attempt was an ambitious cut-and-fold arrangement made from card. It looks something like a giant matchbook.

While it works pretty well, it doesn't stand up to much wear, and the cutting and gluing is kind of fiddly. So scratch that attempt - if anyone wants to refine the prototype, or would like an Instructable for it, let me know.

So onward to Attempt #2, the one that I'll show you how to build...

Step 2: Ingredients

For this project you'll need:

2 cards
business cards, credit cards, playing cards, or just pieces of generic card.

1 piece of craft foam the size of your chosen card
Every home should have some. Available at craft suppliers and stationers everywhere. Sometimes available as cheap off-cuts.
In my experience this stuff is normally the same thickness as an SD card, but check to be sure.

Craft glue
Your favourite craft glue.

Craft knife and ruler
Essential tools

Step 3: Cut the Foam

Cut the piece of craft foam to the exact width and height of your chosen cards. If you are using plastic credit cards, you should be able to cut around them. But if, like me, you chose ordinary card, use the metal ruler as a guide instead.

Depending on the type of cards you're using you may wish to round off the corners. As you can see, I just cut them at angles. I'm lazy.

Once you have the foam cut to size, cut outlines for two or three SD cards along one edge. You'll get a closer fit if you cut directly around an SD card, but be very careful! If you're a ham-fisted oaf, line the metal ruler up along the edge of the card, then use that as your cutting guide.

If you decide on three slots, start with the two outer slots, then center the third one between them. This avoids having to make careful measurements. For a standard credit card size, the outer card slots should be about 4mm from the sides.

The top edges of the SD cards should be flush with the edge of the foam.

Step 4: Adding the Back Panel

Cover one side of the foam insert with craft glue. Try to use as thin a coat as you can. Make sure you glue right up to the edges.

Place the foam insert onto one of the cards. Press down hard to get a good adhesion, and wipe away any excess glue.

Slot in some SD cards to ensure that they fit perfectly. Slide the four 'prongs' of the foam to the left or the right while the glue is still a little sticky to make adjustments. This is an important step - if you miss it out you could find later that one card is loose and another is too tight.

Step 5: Finishing Off

Next, cut three notches into the card as shown - these will allow you slot the cards in and out easily. If you have fat fingers, make the notches bigger. Obviously this is more difficult it you are using plastic cards, but a few repeated cuts should do the job.

Then place the second card underneath and, using the first card as a template, cut the same three notches in that as well.

Optionally, don't cut notches into the second card. But when you insert the SD cards later, make sure that you do so with the thumbnail slot uppermost - otherwise you'll have trouble getting them out again.

Step 6: All Done!

Finally, glue the front panel onto the foam, insert some SD cards to ensure the foam holds its shape, then place under a heavy (but not card-damagingly heavy) object for a few hours.

To improve the lifespan of the card holder, you may wish to consider a layer of duct tape. Wrap narrow strips over the four 'points', trim away the excess, then wrap a band of tape horizontally around the entire card holder. This will protect the whole thing from being pulled apart by rough handling.

The final image shows a cut-down version (for minimal space usage) - I particularly like these cards - simply wave the card in front of people you consider to be excessively fashion-conscious.