keep on the left side

keep on the left(-hand) side

To remain on the left-most side (of something, especially a road or path). Turn right and walk toward the Main Street Bank, keeping on the left-hand side of the road as you go, and you'll be sure to see our shop. I always have to remind myself to keep on the left side of the road when I drive in the UK.
See also: keep, on, side
Farlex Dictionary of Idioms.

keep on the left(-hand) side (of something)

to stay on the left-hand side of something. Please don't keep on the left side all the time when everyone else is on the right! In England you keep on the left-hand side.
See also: keep, left, on, side
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • keep on the left(-hand) side
  • take a hard left
  • hang a left/right
  • left and right
  • leftleft
  • hang a left
  • be left to (one's) own resources
  • device
  • resource
  • left to your own devices