Decorate the tags: First, do something arty to the tags, so you have a background for later. I colored mine (yesterday) using watercolour crayons and baby wipes then stamped on them. I simply dabbed an ink pad onto the tags in the example. Work on one side of each tag completely, then turn them over and do something at the top of the tag around the hole.
Fold the tags: Lay the tags on your workbench with the holes at the top (short edges at the top and bottom). Fold each tag so that the bottom edge touches the bottom of the ring (hole) reinforcement. In other words, do not fold the tag perfectly in half; fold it so you have a narrow tab.
Create the booklet: Open the tags out again, and lay them face down (undecorated sides up) on your workbench. Spread glue on the smaller flap of the (undecorated) back of the first tag. Stick it to the larger flap of the (undecorated) back of the second tag. Repeat until you have only one tag left.
Make the cover: The final tag will become the cover of your booklet and will cover the spine folds of the other tags. As you work, you'll see that you have to glue the final tag on to what was your first tag. Glue the small flap of the first tag to the large flap of the final (cover) tag.
Cover the spine: Judge how much tag you'll need to cover the folds, then score a fold. Stick a strip of double sided sticky tape onto the tag where it will cover the spine folds. The sticky tape provides better adhesion than glue here. Spread glue on the remaining part of the cover tag and stick it down to form a booklet. Apply pressure to the spine to make the tape stick as firmly as possible to the folds.
Embellish: All that remains is to embellish the journal as desired. As well as a writing/visual journal, this would easily make a nice little friendship booklet or phone list. It's also a suitable format for decos. If you cut your own tags, you can scale up or down as desired.