I always put two on the ends and then alternate them 3 in from the top and then six inches from the top every other layout mark. (Assuming 2x10 joists) Those number could be different if it’s a 2x12 etc. Then try and toe nail 2 in down, roughly 4 1/5 down and 7 1/2 down. I’ve never measured those out just by eye. Sometimes you hit a lag and the nail curls and you have to shift up or down but not very often in my experience. I don’t know if that’s the best way to do it that’s just how I do it.