Olympus OM-D E-M5 Review: Digital Photography Review
Step 1: Go to Custom Menu Function that show "Gear Icon"(bottom left or no.4 liner on left counting from top)
Step 1.1: If you don't see the gear icon in your menu, probably is because you didn't set the display mode "on" under "Menu Display" (go to the "spanner icon" and on the 4 liner counting from top on right in the image below), if not ignore this step and go step 2
Step 2: Once you get into Custom menu look out for "D: Disp/Beep/PC", by then you should see Display Grid Off or On on first page 5 liner counting from top on right
When Display Grid On, there are option of:
• 6x4 grid
• 3x3 grid
• Crosshair grid
• Diagonal grid
• 16:9 (movie shooting) guides Allows various grid options to be overlaid on all live view screens
Really hope this info is detail enough to pin point your problem. Resources from dpreview.com