You're unlikely to be able to make the sofa inhospitable to the cats without also making it inhospitable to yourself, but there's steps you can take to minimize the damage they'll do.
Ensure they have sufficient approved scratching surfaces; if they don't have many yet, add more before you get the sofa, so they get used to them and their locations, and are less likely to go looking for additional surfaces.
Discourage scratching on target surfaces (typically the corners, back if accessible, and sometimes the top of the sofa) with materials they don't like. These include double-sided tape (often sold under the name "Sticky Paws"), aluminum foil, and heavy plastic sheeting (similar to what's used for office chair mats). Depending on how clever your cats are, the clear materials are better, because they won't be able to easily see if and when they're removed.
Additionally discourage targeting those areas by putting a scratching post nearby. You may also need to redirect them if you catch them scratching at an unprotected part of the sofa. By having the appropriate target close to the inappropriate one, it's much easier to redirect their attention.
If there's a corner they just won't stay away from, consider a long-term solution. It may not look as nice as the untouched sofa, but it'll certainly look better than a shredded one. Look into plastic corner protectors as a way to discourage interaction, or try a sisal scratching mat (like the LURVIG mat sold by Ikea) attached to that area for a durable, appropriate scratch spot.
And if all else fails, find a way to embrace concealing the damage; there are many examples of how to use lace, fabric, or other techniques to disguise damaged corners and surfaces on a sofa that can look quite nice when finished, and add some unique personality to your furniture.
