Baby shopping

So my mother in law claims she would have a baby shower for me ... but I don't want to wait for a baby shower to start buying stuff... I'm pregnant with my first baby, I'm due February. When should u start buying diapers, blankets, shampoo, etc ( reason why I'm not trusting her is bc she had mentioned she would do a wedding celebration and it's been 3 years and it hasn't happened haha. Also her daughter, my husbands twin sister, her wedding is in February so I'm sure her priority it's her daughter who is finally getting married) I could care less about the baby shower but I need some advice ... thank you all ! 🙂