I am starting my first campaign as GM tomorrow with a bunch of people who never played and I am real nervous.

I am starting my first campaign as GM tomorrow with a bunch of people who never played and I am real nervous.

I am starting my first campaign as GM tomorrow with a bunch of people who never played and I am real nervous. I have an idea how to start. What i thought would be cool is throw them into it. Have them enter a dungeon and find a really hard boss that will wipe them all out but one. the one left will be told of impending doom and then they will all wake up in the town they will start from. Apart from that I have custom items and a general map with blanks.

The idea is that a group of people will be trying to open a portal to release the dangers inside and slowly take over the world. I assume this would be the campaign front?

How do i go about making other fronts or adventure fronts. Do i pick from the backstories of the characters when i hear then. Also how do you continue from the point i left off, just ask what the characters will do?

Are there any good pointers i can get for my first campaign?