Burnish all the score lines, on DSP it can be difficult to see the score marks, so be careful that you're following the score markes.
Put the un-scored side at the top, as this is the opening of your bag and will help you visualise your finished. On the bottom of the bag, on both sides, cut on the score lines up to the intersecting score line. On one of the pieces you need to cut off the two bottom corners.
If you are making your bag out of cardstock, this is the stage I would do any stamping I wanted to do to decorate the cardstock.
On the piece that has the corners cut off, put sticky strip on the three outer edges, as shown in the photo. Make sure you add the sticky strip to the side that you want showing on the outside of your bag.
If you are a bit nervous of sticky strip as it is a very strong adhesive, then, after you've removed the protective red backing, run a line of Glue Stick over the sticky strip as this will allow you to be able to play with your positioning a bit before the strong adhesive on the sticky strip takes over. Alternatively, use Tombow Mono Multi Glue, I just prefer the sticky stripe as I seem to get into a mess when I use the Tombow.
Start sticking your two pieces together, I like to start with the outside edges as I find it easier to line up this way.
There are lots of different ways to add handles to your bag. For this one put ribbon handles on either side of the bag. To help me with my placement I made a little template so that I could be sure the handles would be spaced the way I wanted them.
I measured out about 25cm of ribbon, cut the ends at a diagonal, which helps with feeding the ribbon through the holes. Once threaded through, I tied a knot in the end, cut the ends of the ribbon to tidy them up.
If there is anything in this tutorial that is not clear, then please let me know, I really want these to be easy to follow.
Thanks & enjoy your bag making :o) xx