If you help a turtle across the road, move it in the direction it was already heading. Never turn it around.
It's turtle season. Females are crossing roads right now to reach nesting sites, and they know exactly where they're going. If you turn one around "toward the water" or "back to safety," it will just try to cross again the moment you leave.
If it's safe for you to stop, pick the turtle up by the sides of the shell, keep it low to the ground, and walk it across in the same direction it was facing. Don't relocate it somewhere "better." Turtles have small home ranges they spend their whole lives in, and a relocated turtle will often wander trying to get back, crossing more roads to do it.
One exception: snapping turtles bite and have long necks. For those, slide a car mat under them and drag it, or lift from the very back of the shell near the tail, never the front.
The turtle knows where it's going. Your only job is to get it to the other side faster.