settings.py

CHECKOUT_STEPS = [{"template": "billing_shipping", "url": "details",
                   "title": _("Details")}]
CHECKOUT_STEP_FIRST = CHECKOUT_STEP_PAYMENT = CHECKOUT_STEP_LAST = 1
if settings.SHOP_CHECKOUT_STEPS_SPLIT:
    CHECKOUT_STEPS[0].update({"url": "billing-shipping",
                              "title": _("Address")})
    if settings.SHOP_PAYMENT_STEP_ENABLED:
        CHECKOUT_STEPS.append({"template": "payment", "url": "payment",
                                "title": _("Payment")})
        CHECKOUT_STEP_PAYMENT = CHECKOUT_STEP_LAST = 2
if settings.SHOP_CHECKOUT_STEPS_CONFIRMATION:
    CHECKOUT_STEPS.append({"template": "confirmation", "url": "confirmation",
                           "title": _("Confirmation")})
    CHECKOUT_STEP_LAST += 1