imo, the secret formula to waking Jing up {initially} --
are the sweet little kisses to let Jing feel her presence {kiss on the eyes, nose, lips like Jing did for her during the cherry blossom scene although we know her case is different coz she was in a killing formation},
XY's healing blood ofc, the way she fed him the medicine so it won't spill, ?
and her reminding him of their days in the garden in and confessing that she knew how much he restrained himself from kissing her, avoiding her even, and how she liked teasing him for that, and how he turned into a wolf. All these helped him find his way back to her {the lamp's light}.
so for this part--
secret formula {for Jing's life light on}= YaoJing love language= physical touch+ words of affirmation+ quality time. *\0/* ??? (^.^)