This one's simple, but I've found it extremely important.
I'm constantly asked by DPs or Key Grips to do things that fall outside of my skillset. The question can take many forms, from "have you done this before?" to simply asking if you're comfortable with the gear. Maybe I've never used this particular jib or dolly(this happened yesterday) or maybe you've never rigged a light or bounce in this particular fashion before, eg. hanging off a building or suspended above the actors.
I don't feel I need to write this, but if you can't do it safely, don't do it. You may get fired, but it's better than killing someone. What I'm talking about here is the ability to learn as you go. Call it improvisation, I call it on-the-job training.
Back to the issue: I've been asked to do/build/operate something that I've never done before. This is actually my favorite part of the job because it forces me to improve, think on my feet, adapt and learn quickly. So now what? My boss is looking at me waiting for an answer and I'm looking at this intimidating foreign equipment. I look at the gear, look back at him, nod and say "I got this."
This is not lying. At worst, this is deflection. More often than not, he's not asking the question you think he is; He's looking for assurance. He has a job for you and he needs to know that you will get it done. So I say I've got this. I've avoided the question as to whether I've done this before, but I've assuaged his fears and instilled confidence in him, and, as a by-product, boosted my own confidence. It's now up to me to do the thing, and do it well.
An example, back in the beginning stages of my career, I was on a music video shoot with a DP I had never worked with. He had no baseline knowledge of my skills or experience. He explained the shot, a 14ft jib mounted on a doorway dolly following a nurse down a tight hallway. I had never built or operated this jib before, but I had seen one similar built once. And now it was up to me to not only build it, but build it on a dolly, a freaking moving platform. I was scared, I'll admit it. Then came the question: Have you done anything like this before? Without thinking, I nodded and said "I got this". Even though I had never done anything this awesome before, I had a basic familiarity with most of the pieces. The shot was coming up in an hour or so, thus the dp left me to my task and took the other grips to light the scene at hand. I was alone, and completely responsible for building this monster.
First things first: lay and level the track. Basic. Done. Next. Throw the dolly on. Done. I spent the next fifteen minutes opening the road cases in which the jib was packed. No user's manual. Fine. Just pick up all the pieces and really look at them. Flip them over. Examine the fittings. Just checking for wear, I said to a curious PM who wandered over at one point. Putting a lot of weight on this, and I don't want any surprises. I suppose this was sort of true. Build the legs. Assemble and level the head. Build the arm, add the weights and balance it. In the end, I ended up both pushing dolly and opping the jib, we got the shot, took the camera off and I disassembled it, piece by piece, just as I had built it. The dp liked my work; he and I have worked with each other many times since, and I have huge respect for him.
My point is this: You don't need to know how to do everything, but keep your eyes open. Learn about the individual parts. Every control arm on every jib is different, but they all do the same thing. Understand their purpose. Trust in your abilities and ask for help or guidance if any is available and RTFM!
When you say "I got this", you're saying to yourself "I don't know exactly how to do this, but I'm going to figure it out quick", but your boss just hears what is important. Remember, he's not asking HAS it been done, but WILL it be done.
Now go do it!
(and be safe, for chrissakes!)
~S