Screen brightness can help. f-lux.com has an app if your display does not dim from the keyboard or display controls.

I also use the zoom function.

I also do better with multiple displays rather than cascading/stacking windows and switching/toggling between them. If I have to remember what is on a hidden window for work open window, I will struggle. But, looking back and forth between two displays is much easier.

It helps me to keep my screen uncluttered. If I am working online where there are ads, I need to use an Adblocker or a Flashblocker to simplify or reduce the stimulation.

If you need to read long lines of text, narrowing the frame so the line length is 80 characters makes reading easier. I've used a character count tool at Character Count Tool - Get The Character Count of Given Text to help me understand what my sweet line length is.

I've used the highlight feature to reverse the color or make black text on a white background show as white text on a blue background. The highlight feature can be very useful as you try to read some difficult formatting and color combinations. I just drag the cursor across to see if I can read with less strain.

Some have found that tinted glasses help.