How can a new A&P troubleshoot intermittent faults under overnight pressure?

[EmmaRT]

I'm a newly licensed A&P mechanic starting my first job at a regional airline, and while my training was thorough on the book knowledge, I'm feeling overwhelmed by the pace and pressure of the actual line maintenance environment during overnight shifts. My specific struggle is efficiently troubleshooting intermittent faults, like a recurring avionics warning light that checks out fine on the ground, within the tight turnaround times we have. For experienced mechanics, what practical advice do you have for developing a more systematic diagnostic approach under time pressure, and how did you build confidence in signing off on complex systems when you were new, knowing the weight of that responsibility? I want to be thorough but not the bottleneck.