What changes for golfers who are blind or vision impaired?

Rule 25.2 covers players who are blind, including certain levels of vision impairment:

• Aide: you may get help from one aide with taking your stance, aiming and advice. You may have an aide and a caddie at the same time and get advice from both. The aide can also be your caddie.
• Setting objects down: you, your caddie or aide may set an object down (such as a club on the ground) to help with aiming or stance, but it must be removed before the stroke, or it's two strokes.
• Standing behind you: your aide or caddie may stand on or near the line behind the ball before and during the stroke, as long as they don't help you make the stroke.
• Bunkers: you may touch the sand with your club right in front of or behind the ball, and on the backswing, provided you don't improve the lie more than lightly grounding the club would. You still can't test the sand or touch it in a practice swing.
• Lifting on the green: your aide, as well as your caddie, may lift your ball without being asked.
• Dropping, placing, replacing: you may give a general authorisation to anyone to do this for you.

If your aide also handles your clubs while you have a separate caddie (other than guiding you, helping with stance or aim, or as a courtesy), you're treated as having two caddies: two strokes per hole.

Source: Rules of Golf (2023), Rule 25.2.