New grads make the best PICS.....well, because they are the ones who will readily accept the job. Learning the ins and outs of your computer system is the easy part, the harder part will be learning to be a "manager."
General advice:
1) Observe for at least the first month. Do not come in and make any changes (unless something is really illegal), or that will get you off on a bad foot. Especially as a new grad with little experience, you don't want to get off on a bad foot.
2) Don't talk personal stuff at work. It's fine to mention if you have a boyfriend/girlfriend/family, where you live, basic introductory stuff, but nothing beyond that. Certainly *NEVER* come to work and talk about problems you are having with a family member or landlord or any problems at all. Conversely, don't participate in listening to your employees talk about their problems, if they try to initiate a personal conversation with you, cut them off gently and give them a task to do (if they are talking personal things with other employees, ignore it unless its affecting work) You should be friendly to your employees, but you aren't there to be there friend.
3) Treat all your employees equally at first. Maybe you've heard bad things about some of them, maybe one of your techs or pharmacists will "warn" you the first day about another employee. Don't listen to gossip or hearsay, treat everyone equally and observe. It's not unheard of for the "bad" employee to warn a new guy about another employee, to take attention off of themselves. After observing for a month, you will have a good idea on which employees need help, and in what areas. Similarly, if you see an employee who isn't doing things right or isn't doing things at all, don't assume they are stupid or lazy--chances are they were never properly trained. It is your job to properly train them (and if they still can't perform after that, well then handle that the way you are supposed to handle a performance issue.)
4) Expect to spend a lot of extra time in the first weeks and months of your job. Not only are you getting a crash course in your specific pharmacy, but also your specific employees. You won't always have to spend that much time at work, but expect to put in extra hours at the beginning.
5) Take copious notes so you never have to ask the same thing twice. Reach out to other managers in your chain. If after the first month you realize there are serious problems in certain areas (as you most certainly will, that is why no one else wanted to be manager in that store), talk to other managers or your DM about suggestions to work on those problems. Implement only 1 change at a time (multiple changes will freak out your employees, and then you won't have any idea what is working or not working.) Along with this, ask lots of questions, anything you don't know how to do, ask. Anything you see a technician or another pharmacist doing that you don't know how to do, ask. Anything that you can't figure out why anyone would do it that way, ask.