Debit The Receiver, Credit The Giver
This principle is used in the case of personal accounts. When a person gives something to the organization, it becomes an inflow and therefore the person must be credited in the books of accounts. The converse of this is also true, which is why the receiver needs to be debited.
Debit What Comes In, Credit What Goes Out
This principle is applied in the case of real accounts. Real accounts involve machinery, land, and building, etc. They have a debit balance by default. Thus when you debit what comes in, you are adding to the existing account balance. This is exactly what needs to be done. Similarly, when your credit what goes out, you are reducing the account balance when a tangible asset goes out of the organization.
Debit All Expenses And Losses, Credit All Incomes And Gains
This rule is applied when the account in question is a nominal account. The capital of the company is a liability. Therefore, it has a default credit balance. When you credit all incomes and gains, you increase the capital and by debiting expenses and losses, you decrease the capital. This is exactly what needs to be done for the system to stay in balance.
The golden rules of accounting allow anyone to be a bookkeeper. They only need to understand the types of accounts and then diligently apply the rules.