As I said, NBA Live 10's Dynasty Mode is basically the same as last year. You can find my review
here, if you're interested.
The trading block screen allows you to choose a player to offer around the league. After selecting a player, if there's any interest from other teams you will be presented with all the available offers. You can cycle through each team's offer and review them (it won't always be very good, quite often the CPU will try and rip you off), from there you can choose to quit the trading block and cancel all offers, select another player to shop around the league, or complete a trade offer. If a player doesn't draw any interest, you'll get a pop-up stating that there are no offers at this time, at which point you will be given the option to select another player or back out of the trading block screen.
The staff ratings are fairly ordinary to begin with, unlike previous games you can't sign a high rated staff member straight away. You upgrade your staff using Dynasty Points, which you earn by completing certain goals according to your team's direction. When you start a new year, you pick a direction for your team (rebuilding, grow and improve, compete for the championship). According to the direction you pick, you'll have certain Dynasty goals such as winning the MVP award or making the All-Star team, which will earn Dynasty Points which as I mentioned before are then spent upgrading the staff.