I made this tutorial a while ago. But got a lot of requests to make it in dutch.
Here it is in english, the next post will be in dutch!
If you can't sew then get you pouch here: http://www.fabrickitchen.nl
First make a pattern. Here are the sizes you have to use for the DS Lite or DSi.
These are in cm.
Cut out the following fabric pieces. The plain green is the lining of the pouch.
I used a seam allowance of 1.5 cm.
Fold the dotted green part like on the picture. This is going to be the cover of the bag for the games. Sew the dotted green flap on of the outside pieces.
Fold the top of the (brown) bag part and sew the top.
Put the bag part under the flap. Put the other outside on to it, like on the next picture. The right sides of the fabric are put together. Sew the bag so it it 17,5 cm long. You can clip the seam allowance now.
Put the right sides of you lining fabric together and sew the bag(17.5 cm long)
Clip the corners and fold the top.
Fold all the seamallowances like on the picture. Put the lining into the outside bag. Now fold the top of your lining and put the top of the outside bag into it.
Do this on both sides of the bag.
Sew the top to the lining, both sides. Put a cord or ribbon through the 1 cm hole on both sides of the bags. This might be a bit tricky, a paperclip will help a lot.
Then you are done!