You can use your sterlizer or bring a pot of water to a boil, put the bottles in and boil for 5 minutes (or per the directions on your particular bottles).
The same way you sterilize plastic ones. You can use an electric sterilizer, a microwave sterilizer, sterilizing steam bags, or boil water on the stove.
Re: HOW DO U STERILIZE GLAS BOTTLES? HELP!!
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