Wash jars in hot soapy water and place in hot water or in an oven on low heat until ready to fill. Keep the lids simmering in boiling water until used.
Prepare peaches by peeling and slicing. (You can shock them if you wish. I haven’t had much luck with this.) As you slice, place into a large bowl and occasionally squirt with lemon juice to preserve the colour.
Make your syrup. You have some liberty here. I don’t like to make mine too sweet so I do about 5 cups of water to 1 cup of sugar. You can change this ratio as per your family's preference. The original recipe I followed had much more sugar. You can also use honey; however, I found they didn’t look as nice and yellow in the jar so I stick with sugar. Add the sugar to boiling water slowly, stirring constantly to dissolve. Keep simmering until you place it into the jars.
Take your hot jars and start filling with peaches until you get about ½ inch of headspace. I go until they reach the bottom of the neck . Throughout the process of adding peaches, run a butter knife or another flat item in between the peaches and the side of the jar to release air bubbles. Do this repeatedly as it will allow you to get a fuller pack in the jars.
Add your boiling syrup into jars, leaving ½ inch head space.
Wipe rims.
Place on lids out of the hot water and tighten the rings to finger tightness.
Place in a boiling water bath canner and return to boiling.
How long you process your cans in the water depends on your altitude so you will need to do a little research. I process my pints for 25 minutes and my quarts for 30 minutes. If I have a mix of jar sizes, I can for the longest amount.