I think that first and foremost, you will need to be diligent in prayer. God will direct you as He probably has in your life to bring you to this point. Be sure and keep your heart open to what He has to say.
That being said, their are a few things that I think you could do that would make your decision more apparent.
1) what are your first impressions of the congregation that is calling you?
2) As you spend time (usually its limited) with the congregation, look for the relationships that the members hold with each other, see how they interact.
3) Who was their last pastor and why did he leave?
The reason why this is important is because if you make the decision to go to this patorate, you will need to know what he has left behind (did he go on to glory, fired, resigned, transfered etc.). This is important to know, that way you know how to handle the congregation (are they morning, bitter, confused, divided etc.).
4) Is the congregation vibrant and strong? Are they constantly looking to evangelize the lost? What is their focus? What is their ministy?
There are other things that you must consider as well
1) Location. (generally, this is not an issue, but if you have a preference that may help to make your decision)
2) If your married, work with your wife, she too may have some insite about the call to that location.
3) Is there a parsnage, or will you have to rent an appartment, house?
I know that most don't like to talk about money but if your just getting out of seminary, its a consern
Can they pay you enough to help pay your student loans and give you an honest wage for the preparation of ministry and the ministerial work that you will be engaged in?
Health insurance?
travel compinsation?
Time off? (pastors do need a little time to themselves occationally
)
I'm certain that I could continue with this list, but I do want to give others a chance to share what they can about the subject. Just remember, details are important, but ultimately, shepherding the flock is your call, it's what God has called you to do. You will know
thats my
Blessings,