I've been working at a multinational American tech company for about 2 years now. These are the things that I've learned from my tech lead:

• “Communicate like a 5-year-old." - Clarify everything. Explain things as if you're talking to a 5-year-old.
• "Laugh at the stupid things." - Many times you'll face miscommunication, bad engineers, or just overwhelming processes which can be really stressful. You need to be able to laugh at these things.
• "Do your best, do what you can, and if it’s too much, well… dahh... sorry." - Not everything is within your control. Don’t overwhelm yourself with impossible tasks. Just try your best and let go of what you can’t control.
• "Years of experience often doesn’t mean anything" - Experience on paper doesn’t always reflect actual competence or skill. I've met many incompetent developers despite their years of experience.
• "You have to be pushy, assertive" - Be like Donkey from Shrek 2: ask the same question repeatedly if needed. It might be annoying, but it gets results.
• And the most important: "You only truly learn when you suffer with an issue long enough to never forget the solution."