1.) Really, really, really ask those dumb questions in the first week. Everyone will tolerate it and even expect it
2.) Learn the basics of your new domain / industry top-down asap. Meaning: understand for what your company gets paid for, understand the basic process how it gets delivered, understand the strengths / weaknesses of your company. Know who the key customers are and what they really want. It’s often the new guys who are empowered to challenge those high-level topics while everyone else takes it for granted (and often have the wrong idea in mind)
3.) Always ask a question / say something during the first five minutes of a meeting. It just gets harder and harder afterwards. But as soon as you asked you’re in the game
4.) Bring in experience from the past but try to take the extra mile of translating it as much as possible to the new situation (“at my last gig we did... I understand that here we have... however I see further potential in...)