For your ¼ inch Hardiebacker use 1 ¼ inch screws. Now tape the seams making use of fiber mesh tape. Use a flat trowel and thinset to go over it. Let it heal overnight prior to tiling. Tile with identity goes a good distance in upgrading an all-white bathroom. Here, https://kameronrocnx.blogofoto.com/67790563/the-ultimate-guide-to-bathroom-tiling