Here's another pro tip: if you're using an egg timer (yes, that's a thing!), make sure to adjust the time based on the size of your eggs - you don't want to end up with an egg that's overcooked or, worse, undercooked! And, if you're feeling extra fancy, you can try using a thermometer to check the internal temperature of the egg - it should be around 160°F to 170°F, but don't quote me on that!
How Do I Know If A Boiled Egg Is Done at Thomas Schnell blog
But, let's get real for a second - the best way to tell if an egg is done is to simply check the package for instructions, because, let's face it, the egg farmers know what they're doing! Or, you know, you could just ask your granny for advice, because she's probably been boiling eggs since the dawn of time!