Remove all green parts of the stem so that you are only left with the yellow petals. This is the pain in the butt part, but worth it to remove any chance of a bitter taste.
Pour boiling water over the petals and let them sit for 24 hours
Measure 3 cups of dandelion liquid (if you have more than that, freeze it and make another batch later).
Add in the lemon juice and pectin and bring mixture to a boil.
Add in the sugar and stir constantly. You'll want the mixture to be at a high boil for 2 1/2 minutes.
Turn off the heat and skim the surface of any debris
Pour into warm processed jars.