For a pro look, you might want to equip yourself with a curb trowel from Amazon or your local hardware. Alternatively, you can install concrete edging stones, such as these overlapping Bullet ...

A hate for edging can spread like a ... along exterior walls is the result of concrete contractors having to hand-finish edges because their power trowels couldn't get close enough to the edge ...

trowel at the 2020 World of Concrete in Las Vegas ... arm rests, and an edging kit that enables the LD6 to finish closely against walls. Each accessory kit is designed for quick field installation.