Question: how to frame a door?
Answer: Measure the distance between the king studs (door width plus 5 in.). ... 
TIP: Mark and measure at the same time. ... 
Mark the cripple locations. ... 
Keep edges flush. ... 
Transfer the layout marks to the header. ... 
First, fasten the header to the king stud. ... 
Add the cripples before the double top plate.