Use a thermometer and the temperature will guide you. The higher the temperature you reach, the thicker the marmalade will be!
Wash your citrus fruit then place in a big pot of water so that they are completely submerged. Boil them until very soft and pliable before slicing them.
Slice the soft fruit and remove/discard any seeds. For thick cut marmalade, slice thick. For thinner cut marmalade, slice thinly.
Cook it to the marmalade setting point
Combine the sugar. all the sliced citrus fruit & juices. Boil it in a big pot on the stove until you reach the desired setting point.
Transfer the marmalade to clean jars, cover with lids (finger-tight), and seal them using a boiling water bath for 10 minutes.
FIND OUT EVERYTHING YOU NEED TO KNOW ABOUT MAKING MARMALADE