Before embarking on a new job or a new sector, what do I need to know or what to prepare myself for? Would the things to note differ for when it's for a new job and when for a new sector?

Humble and open mindset...

If you’re going into a new sector, those hiring you will know you don’t have the background. Focus on learning what you can about the sector from a high level. If there’s an aspect of it that you particularly like, do a deep dive and learn all you can about it so you can talk with some level of understanding and enthusiasm when you get the chance.

If you’re going into a new job, learn all you can about the new company. Identify the company’s strengths and weaknesses and identify one or two that you are interested in. Research how you can contribute to the strengths or fix a weakness. Solving the problems of your superiors is a sure-fire way to get promoted. Everyone loves it when someone makes their lives easier.

If you’re especially adventurous, request to be assigned to the most difficult situation the company is facing. If you succeed even a little bit, you will be seen as having done something good, plus you’ll be seen as someone who is not afraid to take on hard projects. Most people run away from hard projects. Most people don’t get quickly promoted. Don’t be like most people.