Like I said, and others have their own methods, I use a shallow baking pan suspended over the sink, the sides are just wide enough with my sink to strattle the sink.
I use a Peterson film tank when developing color film, it has an agitation stick and I can leave the film tank in the baking pan during processing. Though I do remove the film tank from the pan long enough to tap out bubbles.
My Yankee Clipper tank I use for 16mm film doesn't allow for inversion so it has to be agitated using the agitater/thermometer it came with.
My baking pan is maybe two and half inches deep.
I've gotten good results using this method.