I bought some Kleenex packs from Poundland, and worked the best measurements for this make as some packs are slightly different size (but fairly negligible so I wouldn't worry too much).
I have only found packs with top opening now.
I have set this as a mini challenge to a few of the girls on the forum, you should have received 2 templates, fabric and a length of bias binding. I was going to send the tissues, but think the package would have gone to bigger than a large letter, so I hope you have a pack somewhere in the house.
So start with cut a piece of fabric 155mm (6 and 1/10 inch), by 140mm 5 1/2 inches or slightly more as this is your seam edges.
A length of bias binding to match (28mm /11inches)
Iron your bias binding exactly in half.
If you are going to make a few I recommend that you cut a piece of paper for your cutting template and a piece of card for your folding and stitching template .
Folding and stitching template: 5x3inches or 129mm x 78mm
Mark a line half way along the length, you can see mine in the picture. This template will be the finished size of the sewn pouch, and the line where the bias edges meet.
Then just machine sew carefully along the edge of the bias binding, you don't need to be really close. Right side up
I use a straight stitch, nothing wrong with using a zig zag or something fancy.
If you want to have a go at hand sewing, You could put the bias binding rights side together. Stitch along the crease, then fold under to the wrong side and slip stitch along.
Fold the edges in using the template as a guide, pin or peg.
Mark your seam allowance along the edge using the edges of your template. The edges will be your stitch line,
Then it is just a case of straight stitching using the template as guidance.
Optionally you could zig zag the raw edge. I have a lovely foot for the sewing machine that makes edging simple.
I have also made some with thinner fabric and doubled the width, and I did not bother to actually join the ends, just putting them together inside at the back, and just put some ric rac on the edge for a change.