The most important is to have good reloading manuals and use them. Most seasoned reloaders have dozens. Always verify load data with at least two known good sources. Never trust unknown reloads or components. Never trust an opened powder container. I have two scales and often double check loads on both to verify I didn't set the scale wrong. I highly recommend using the loading block method when beginning, that way you can visually inspect the powder level before seating bullets. I buy a lot from Midway, I've also used Midsouth and Natchez. Probably best to buy components from the big box stores to start out . If you can buy powder locally you're usually better off as the Haz-mat fee is pretty steep for a couple pounds of powder. Be careful with primers, they are more powerful than their size would indicate. I would always wear eye protection while reloading. No smoking, no drinking, clean up powder spills immediately. If you want to see something impressive, dump a pound of powder on the ground in a safe area and set it off. Don't squat over it with a book of matches either, give yourself a good 10 ft of clearance. Don't allow yourself to be distracted while loading. Don't allow yourself to be distracted while loading. Don't allow yourself to be distracted while loading. Y'up that's what I said, Don't allow yourself to be distracted while loading.