Ask them in Discovery, to remove bias from, inform and steer your desktop research, user research participant recruitment and user interview scripts.
Ask them in Alpha, to take out bias from your prototype design. This could be: removing references that not all cultures would understand, not making gendered titles a required form field, not making assumptions about digital capabilities, like being able to upload a photo or use Google maps.
Ask them in Beta, to recruit a wide range of user research participants and to make sure the prototype will work for people using a range of devices, browsers and access technology.
Ask them at launch to make sure any launch events are accessible by all. To user acceptance test across a range of devices, browsers and access technology.
Ask them after the product, service or site is live, to maintain content that is fit for all, gather feedback from a range of users and apply new insight.