Do not use open-kettle method. Use a boiling bath canner or pressure canner to be safe.
Do not seal jams, jellies, preserves, and butters with wax or paraffin which allows harmful mold growth.
Do not use recipes from celebrity chefs and unreliable internet sources which may use unsafe, outdated, non-research-based methods.
Do not invert hot jars of jam, jelly, etc.
Do not use microwave oven, electric oven, slow cookers, convection oven, dishwasher, sun canning, or other methods besides a boiling water bath canner or pressure canner. These methods can be extremely dangerous and are not allowed for processing. The only safe and approved method is using a boiling water bath canner or pressure canner. However, if a pressure canner is used in a cottage food operation, it must only be for properly acidified and permitted foods, not for low-acid foods.