Liquid chlorine bleach has a relatively short shelf life - less than 6 months from the time the jug is opened.

To be able to have a 5% chlorine solution (for water or other disinfection) it's possible to make your own 5% (more or less) hypochlorite solution.

Chlorine bleach (Chlorox, Javix for our Canadian friends) is 5% (more or less) sodium hypochlorite. We don't care one way or the other about the sodium part in it, all thats important is the hypochlorite. Thats what does the disinfection.

Pool shock chlorine is available in dry form, from many locations - pool supply stores, the grocery store (maybe), etc. It usually comes in 1 lb plastic bags, and is around 75% calcium hypochlorite. It's pretty inexpensive, too - a few dollars a bag. Like before, we don't care one way or the other about the calcium part of it.

If you take about 75 grams (two ounces by volume) of your typical pool shock chlorine (calcium hypochlorite) and mix it with a liter (quart) of water, you will have a mixture that is about 5% hypochlorite. You can use this like you would use Chlorox bleach, further dilute it for disinfection or water sterilization, even bleach your white clothes with it. If you have a precision-enough kitchen scale that can weigh out the 75 grams (1157 grains, or 2.6 ounces) weigh it out, otherwise an 1/8 cup dry measure measuring cup plus 2 tablespoons should be close enough.

The mixed solution will suffer from degradation the same way that regular bleach will. The dry powder is pretty stable (it will lose 3-5% per year) but if kept cool, dry, and sealed it should stay potent for quite awhile. Keep it sealed in non-corrosive (plastic) containers and bags, and expect to have to replace the containers from time to time: Bleach is a very potent oxidizer and attacks a LOT of stuff.