How should a new professor sign their name in emails to students? I just finished my PhD and am starting an adjunct position at a local community college.  I was responding to my first email from a student when I came across a problem I've never had before: I don't know how to sign my email.

Some options I've considered are:


First Name: this is how I've signed every academic email my whole life.
First Name Last Name: I have signed business, legal, or other official letters like this, and I suppose since this is my first job I could sign it the same way?
Professor Last Name: this makes the most sense because that's what I want to be addressed in the classroom, but I have never seen a professor write their title out like this.
Initials: I always thought professors signed their emails like this to shave precious seconds from their inbox time, but I'm now suspecting it has more to do with avoiding making the decision of how to sign.


I'm sure the best answer isn't going to be one of the above suggestions.  No matter what I pick, I want to be consistent, so there's no confusion as to how I should be addressed.



Edit: this is in the US.
Sign as you wish to be addressed by the recipient. When I sign an email with my first name, I am giving the recipient permission to address me by my first name. I almost always sign off with my first name, but in the rare instances that I don't want them to address me that way and do want to retain more formality, I use "Dr Firstname Lastname" instead. If I'm really feeling ambivalent, I'll use "Firstname Lastname", which I feel leaves the decision up to them.

I usually also have my full name with title and contact details in the sig at the bottom of my email, separated from my sign-off by a line containing only "--". This is so my contact details are handy, but also for clarity -- even if I am giving them permission to use my first name, it is sometimes useful for them to know my position and qualifications.