Being a crafter I work with glue a lot.
Some of my favorite glues don't have a thin nozzle . If the nozzle is not thin it's hard to apply the glue neatly to small areas.
Enter the tape nozzle. Made with a small piece of plain old cello tape.
Not original, I saw it on Youtube.
It will be easier for you to see it then read how to make it.
So here you go--it begins around minute 2:35.
Here's the direct link to the video: