Mental vigilance.

Vigilance is alert. Focused. Sharp and attentive. 

But vigilance divorced of method only leads to attachment or aversion.  You need to rely on discipline and mindfulness in order to gain freedom in your situation.

Discipline gives you form.  It is your posture.
Mindfulness brings you back when you have strayed.

When you combine discipline and mindfulness with mental vigilance, you will easily carry out your aims.  You will know what you have to do and have the vehicle to get there.  You will not tire and giving up is not an option.