To avoid a repeated tile effect when importing images as textures in Design, make sure the image is tileable and seamless.
You can find seamless textures online or create your own using image editing software (e.g., Photoshop).
Use images designed for repeating patterns, and choose textures available in different sizes and shapes for better backsplash results.
You can achieve the best results for any backsplash design using the wide selection of tiles and mosaics available in the Texture Editor. To access it, right-click on an item and select Attributes > Variables > Textures.
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