The past couple years, I've found Michael Palmer's advice about record keeping very handy. As you learn and grow more successful as a beekeeper, you may find yourself going well past three or four hives and you'll start forgetting important details such as:

Queenright?

Laying well?

How much did it weigh last?

Where did the queen come from?

What day did it swarm?

When did I create this split?

Need to feed?

Mite test results?

You could carry a notepad around with you, but you'll see how complicated that can be very quickly. And, there'll come that day you leave it at home or the dog eats it.

I trust this helps you as it has me. :)