This is my first tutorial on Craftster, so be nice to me.
The tutorial is actually old, but I haven't published it in English before. This way of thinking is very versatile and can be adapted to a lot of projects, but I choose to illustrate it with this little case. Perhaps there's another tutorial for the same thing somewhere around here but I haven't seen anybody suggest sewing like this so I hope you like it. It has saved me a lot of time at numerous occasions.Lined bag with 2 seams
Cut two pieces of equal size in your fabric choices.
Fold/press the seam allowance on one of the short sides. This will be the upper edge of the bag's inside.
Fold/press to mark the depth of the bag, right side in. The lid part will now stick up.
Put the two pieces on top of each other with the folded seam allowances inwards.
Baste if you want/need to.
Sew along the three unfolded sides.
Cut the corners. (Zigzag the raw edges if you want to.)
Turn the bag right by first turning it through the hole in the bottom...
...and then fold over the outer fabric.
Top stitch around the edges.
Here I used a snap button for closure. Done!
English is not my first language, so please correct me if I'm not using the correct terms or if something needs clarification.