The first thing you will need to do is prepare the canning jars, lids, etc., and peel the peaches. Remove seed from peaches, then slice. Place all peach slices into a large bowl. Treat peaches with Fruit Fresh or lemon juice to prevent browning.
Prepare and sterilize canning jars. I like to place them in my water bath canner filled half way with water (on the elevated rack), and let them simmer (NOT boil) while I am preparing the peaches. Have all your canning utensils, jar lids and rings prepared and ready to use, according to manufacturer instructions and standard USDA canning guidelines.
Prepare syrup for peaches, by combining sugar and water in stainless steel saucepan. Stir, and bring mixture to a boil, on medium high heat. Stir often until sugar dissolves. Turn heat to Low; keep syrup warm, stirring occasionally, until ready to fill canning jars, stirring.
Warm peach slices in large stainless steel pan (one single layer at a time) on medium-low heat. Cook ONLY until just heated through (about 1 minute), then repeat with remaining peaches. Remove peaches with a slotted spoon; pack peach slices into hot, prepared canning jars, being sure to leave 1/2 inch headspace in jar. Ladle warm syrup into jars, leaving 1/2 inch headspace.
Remove air bubbles from jars; adjust headspace, if necessary, by removing or adding syrup. Wipe rims of jars clean (to help jars seal properly), place flat lids on jars, then screw the bands on to fingertip tightness. Carefully lower jars (on rack) into simmering water in canner. Make sure the jars are covered completely with water (at least 1-2 inches over tops of jars). Cover. Bring water to a boil. Process pint jars for 20 minutes, and quart jars for 25 minutes.
Once jars have been processed, turn off heat; remove canner lid. Wait 5 minutes, then carefully remove hot jars with canning tongs to a dish towel (don't put the hot jars straight onto a counter top-this could cause jars to crack). Let jars cool (you should hear the jars "ping" as they seal) for 12-24 hours.
Once the jars have sat, undisturbed, for 12-24 hours, check to make sure the jars have sealed correctly, then wipe down jars, label them, and store them in your pantry! I remove the screw bands for storing. Any jars that did not seal properly should be refrigerated, and used within a week. ENJOY!
TIP FOR REMOVING PEACH PEELS: Place 3-4 peaches at a time into a large pot of boiling water. This helps to loosen peel. Only let the whole peaches stay in boiling water for one minute, then remove. As soon as you remove the peaches from boiling water, immediately place them in a large bowl of ice cold water (really cold). This will stop the "heating" process quickly. Remove peaches from ice water and easily pull the entire peeling off the peach, leaving a beautiful round peach, with no skin. Repeat process with remaining peaches.
Canning Sliced Peaches https://www.thegratefulgirlcooks.com/canning-sliced-peaches/