Income inequality within a relationship can also make it hard to decide what is household income and what's your own personal income to do as you like with. Deborah Price, author of The Heart of Money, explains this dilemma: "One of the most common issues I see is that the person who earns less views the breadwinner's income as 'our money,' but considers their own salary 'their money.' If left unmanaged, this attitude can start to fracture the relationship."
Set up a joint account, and then each of you should have a personal account. You could fund the joint account proportionately — if one partner earns 2/3 of the total household income, they contribute 2/3 of their take-home pay to the joint account, while the other partner contributes 1/3 of their take-home pay. Whatever is left over for each partner gets deposited in the personal accounts. Alternatively, you can use an "allowance" system — all take-home pay gets deposited into the joint account, then each partner withdraws a fixed amount each month into their personal account to use as they wish.
Once money is in a personal account, don't question or criticize your partner on how they choose to spend it — unless they are doing something clearly reckless or dangerous. Conversely, if a partner spends all the money in their personal account, they should not be able to dip into the joint account for a personal purchase, unless you both agree to it.