I seem to forever lose those little (often red) tubes that come with my spray cans (normally with lubricant os some sort).
I've tried using elastics, but they often seem to disinegrate, so I decided to print something that would hold the little red tube instead:
Just stick the tube in:
and clip it to the can:
I created the file in OpenSCAD, and set it up to that you can easily customize various parameters (most likely can diameter and tube diameter, plus a few more). You can find the files on thingiverse.