Tags are sorted alphabetically by default. To change the order of tags:

1. Hover over the Tags header.
2. Click on the dropdown arrow to the right of the header name to display settings.
3. Click Sort by drag and drop.

When tags are sorted by drag and drop, hovering over a tag will now display a drag handle to the left of the name.

Now you can reorder your tags by drag and drop:

1. Click and hold to the left of the name to pick up the tag.
2. Drag the tag to the desired location.
3. Release to drop the tag into position.