you can use a cardboard cylinder.

If you need to amplify the sound of your phone…

you can do a trick with silver tape.

If a jar is hard to open…

you can use your phone and a water bottle

If you need a lantern…

wrap a wet paper towel around it and put it in the freezer.

If you need to cool your drink fast…

you can use a soda can.

If you need to boost your Wi-Fi signal…

You can use a zip bag.

If you need to protect your phone from splashing…

use dental floss.

If you need to cut a cake perfectly…