I'm with spacecoast, I started with a lee loader both pistol and shotgun 45 years ago and reloaded plenty of rounds without a manual. Finally bought a manual after 5 years of pounding shells out with hammer, that after I brought a press and dies.
I imagine if you want to eke out that last 50 to 100 fps you might need a manual with some new powder, but if you go with a starting load off a IMR website or pamphlet, you aren't going to get yourself in trouble.
Did I need to take a driver's ed course to learn to drive a car? I might want to get instructions if I'm going to race one however.