Put greens in large bowl with other items
in smaller bowls. Let people help themselves,
or for more control, serve 'Cafeteria' style where someone put what
they request onto their plates.

NOTE:
There is a large country fair here each fall. One of the most popular food
booths
just sells "Haystacks", great big plates of mouthwatering
salads!
They make it for you and start off a base of greens and add a whole
variety of other salad veggies and beans of your choice
but no protein other than the beans, then top it off with a
dressing of your choice....Awesome!