To do Alt + h l h g on Mac in Excel, download and install Accelerator Keys, then press Option, followed by h, l, h, g.
Command: Highlight Cells Greater Than
This is how to do Alt + h l h g on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + h l h g creates a rule to highlight cells with values greater than a specified number. You can choose the highlight color.