[TerryB]

I make a frame from roofing battens and attach 20mm plastic conduit to it using 6mmx50mm roofing bolts. Net over the top and stapled to frame.
Max size about 8ftx4ft so one person can move it.
Can by covered at start & end of year with clear plastic sheeting to extend the growing season.

[Jonajo]

standard fence posts around the corners and a couple down each side, depending on the size. A couple  down the middle of the bed.

Put upturned plastic bottles or pot noodle pots on top, and lay scaffolding netting all over (the plastic or similar stops the netting tearing and wearing away over the long season), peg around the base - job done

[peapod]

Ive got to say...I netted my brassicas every year until last year when I was just so sick of the hassle of removing the netting and pinning it back down, that I didnt bother.
My neighbour of 30 years experience never ever nets his veg and he gave me the ideato try it and see.

They were hardly touched! (Lucky I know )

[shokkyy]

I'm going to try planting climbing nasturtiums up the chain link fence that goes all the way round the veggie patch where I'm putting the brassicas. Maybe it'll keep them happy or maybe it'll just draw them in, but I guess I'm about to find out