The best response I can most likely give is from a Master. You mentioned youth in your last post. I read a lot about Amma this last week end. I came across her practice of Japa as a youth.
As a child Amma practiced Japa constantly. While walking when she forgot she would backtrack and practice again the step(s) she forgot.
“Actions are enjoyable only if the mind enjoys them... the mind alone is the cause of joy and sorrow....with this understanding we can become a witness.” ~ Amma
“Children, do not forget to always repeat your mantra. In the beginning japa should be done in a low voice. Later it can be done moving the lips slightly. Finally it should be done mentally. Thus japa should be practised constantly with each breath. Then japa will go on even if we don’t attend to it, even in sleep.”
https://www.amritapuri.org/6719/mantra-japa.aumThe mantra is the oar of the boat; it is the instrument you use to cross the samsara of your restless mind, with its unending thought waves. ~ Amma