I'm no professional mechanic, but I've wrenched on a few cars on weekends and week days. I'm not afraid to take on a project, but I ask for help when I need it. I don't pretend to know it all, and I like learning from those who know way more than me (which is quite often the case).
Having said all that, I don't try to offer advice on something I know very little about. I only chime in on topics, when someone asks, if I have done the job previously.