No Leaks
This trick is great for anything staying in a hotel and flying on airplanes. Before leaving, make sure all of your shampoo and soap bottles are closed securely. This means double-checking to make sure the caps aren’t open and are tightly screwed in.
For extra insurance, you can unscrew the cap and over the bottle’s opening with a sheet of plastic before screwing the lid back on. That way, if the cap does tend to leak, the contents will have to break through the plastic before spilling all over the inside of your suitcase or carryon bag.