I'm assuming this is an entry-level manager position (i.e. not a manager of managers). Is this the case? The advice I'm writing is geared towards that (although #1 and #2 still apply, it'd be to a different audience, not the front-line sales employees).
Don't come in and change stuff right away. Observe, get to know how your people work, give it time. Understand how they work, why they work that way, who they are, etc. Spend a lot of time learning and observing at the start.
Do something to gain your employee's trust during this time. Find something that is a problem for them currently, and go fix it. Don't go for something major or hard to change (again, there's a trust-building/learning period), but do something for all of them to build their trust. Prove that you listen, take their criticism to heart, and go make change for better. This is an important first step.
After you've had some time to establish yourself as trustworthy, it's a really good exercise to sit down with your teams, lay out what you expect of your teams, what you commit to your teams, and your rules of engagement. Make it a two-way discussion. Putting the moose on the table, it takes the guesswork out of your employees knowing where they stand, and making it collaborative means you get buy-in.
I use a set of like 9 team values to have this conversation. They are generally pretty obvious things like "Take Action, Even If You Fail", "You are empowered, you don't need to wait for me to act", "No Surprises", "Be Direct and Honest", etc. However, it lets your employees know up front what you expect of them.
Make sure they also always know where they stand. If they go into a performance review wondering how they're going to do, you've failed as a manager. Performance reviews should be a formality, never a surprise.