First of all, congratulations on your new job!
One thing you should remember is that many people make this mistake and must always consider the interests of the boss, but it is very important not to "make decisions for the boss".
Also, the finer the accounts, the better. Every income and expenditure must be signed by the parties concerned, not on their behalf.
In case of major transaction or unable to make clear judgment, the responsible person or boss must be informed immediately.
Compared with other colleagues, this is a superior position. Pay attention to words and deeds, maintain good relations between colleagues, and never look down on other colleagues.
Try to avoid right and wrong. You should be careful what you say and do. This is the default rule of this position.
Others will be supplemented by friends. With previous experience, I believe you can do it well!
Good luck!