Read as many reloading manuals as you can until you know the process. Then practice by making a few dummy rounds. Establish a definite process, follow the process and always inspcect the filled cases before laoding any bullets. A good friend of mine and I were discuessing this the other day. Only one powder on the reloading table at a time. Load only one load at a time. Inspect, using a good light source to ensure there are no double charges. Less that a week after discussing this with my friend, who has been reloading for 40 years without an incident, had two powders out for loading two different rounds, he failed to do his final inspection prior to loading a bullet and blew up a beautiful 29-2 Classsic DX. I have pictures but don't know how to load them.
Reloading is fun and rewarding, following a prescribed reloading process, don't allow interruiptions and you will have a rewarding time loading and shooting.
Derryl