This recipe/make has been around for a long time. Some ridicule it, some turn blue, others sing its praises. You decide, try it yourself.
It is tiny nanoparticles of silver suspended/dissolved in water. Silver, interestingly, is toxic to bacteria.
Step 1: What You Need
two lumps of silver
9v or more battery
Step 2: Wire Me Up Scotty
Wire it all up, as shown. I know it isn't a complete circuit.
Step 3: Fill Me Up Buttercup
Fill the container with water, preferably distilled.
Step 4: Dip
Lower the silver electrodes in, MAKE SURE THEY DO NOT TOUCH.
Step 5: Waiting Game
Go and leave it. Overnight. When it reaches the colour of light pee, it is ready.
Step 6: Use It
Colloidal silver has multitudes of uses. I use it to sterilise knives after use, no pictures though sorry.