Best way to edge a bed?

[JustAnotherDayWorkingAtHome]

I have an existing bed but not edges and it looks a mess with grass encroaching and no clear definition.

I've been reading of all diff ways. Metal edging appeals the most is this easy to do yourself as complete novice? What brand?

I like bricks myself, I gather old bricks from skips (always ask the owner, there's your safety warning) and just arrange. It's free, lasts forever, east to move and non-polluting. Plus bugs like them, enticing the birds in.

Tiles are even better but harder to get.

I would personally avoid plastic like the plague and even metal will rust.

Personally, I much prefer the messy, natural look. https://homesteadgardens.com/how-to-create-natural-edging/