on the Apple Menu in the upper left corner of your screen.
drop-down menu, LOCATE Control Panels.
the arrow across and down with your cursor,
and CHOOSE (click on): Monitors.
VERSIONS of MAC OS may say "Monitors and Sounds"
at this point...
If that's what YOUR Mac says, then CHOOSE "Monitors and
Monitor window will open.
"Resolution" on the window, and click to select
the new resolution.
MINIMUM screen resolution of 800 by 600 pixels is highly recommended,
although viewing at a HIGHER resolution is also fine!
You've ADJUSTED your screen resolution!