Temp needs to be under 200 F.
A lot of folks will prop the door open an inch.
I use the following seasonings, but i like mine kind of Mexican.
black pepper, Lime, Tequila, chili powder, oregano, and garlic. Mix all that in a blender with lots of salt. You could probably google how much salt per pound of meat on some kind of jerky forum.
Minus the tequila is the same mix I use on skirt steak for fajitas and on chicken thighs on the BBQ.