Jars: their are two types of jars (NZ). The old agee jars have an extra, thick glass rim about a centimetre below the top and need gold rings to screw down the seals, the 'new' jars need green rings to seal, see second picture. I inherited mine but I have often seen jars and rings in op shops. Perfit seals can be bought at the supermarket. Jars need sterilising immediately before using, I wash and then rinse them in very hot water and then put them in the oven at 75 degrees C upside down on the bottom rack the top rack may need to be removed . when they are dry they are ready. I get them out and fill them one at a time, as they are now very hot I use a rolled up teatowel as in third picture to hold them. Once they are filled with hot bubbling stewed fruit i place them on a wooden suface (a cold hard surface may cause the jars to crack). I use a small (1 pint / 1/2 litre) pyrex jug to scoop out the fruit from the pan and into the jars as this fills them quickly and easily.
SealsI have another small pot of water boiling on the stove, before I get a jar out of the oven I place a perfit seal in it (to sterilise). Once the jar is full to overflowing and placed on wooden surface, using tongs I place the seal on top and screw on the ring. I tighten it using a teatowel as it gets hot. As I fill jars and place them on the wooden surface I make sure they do not touch each other as I've been told this can also make them crack. As the jars cool the perfit seal should bow in the middle rather than being slightly raised, this shows It has successfully sealed.
Basic Fruit Bottling
Water I usually add as little water as possible just enough to cover the bottom of the pan well and bubble up through the fruit as a lot of juice comes out of the fruit.
Sugar i add sugar to taste after fruit has cooked slightly as I understand this gives more sweetness for less sugar added. Also I barely make it sweet as the longer the bottled fruit is stored the more the sugar content increases.