In my glider the gear up position is
marked with hot pink duct tape as well as
the landing flap position and the spoiler
and gear handles as additional reminders
to check the gear.

There's a 4x4" green vinyl square at the
gear down position.

The gear handle is tucked down by my
thigh when up. It's now easy to see it's
down.

The LS gear is even better as it will shred
your knuckles if you pull spoilers with the
gear up.