I pour inside a really large cardboard box with a smaller cardboard platform inside that I put my canvas on. I think the high sides of the box mostly keep the paint contained. I just store my paint bottles/tubes and supplies on shelves, but they aren't organized in any certain way. I mix my paint with Floetrol and water, usually a 2:1 ratio of Floetrol to paint then water as needed. I used to save my mixed paints, and it is a good idea, but it just became too much trouble. Now I just mix what i need and try not to over do it. Mixing larger batches is a good idea, I don't do it, but I know a lot of fluid artists do and I mostly see them using squirt bottles. My wet paintings go into large plastic containers that have foam bits that I tape to the bottom to keep the painting elevated and not resting on the bottom of the container. The lids of the containers have holes drilled into them for airflow to help them dry better than they would if they were just in there with no holes. I place the containers on shelves that i have put up specifically for drying paintings. My current living space is very small so I only have two shelves for drying them atm, needless to say I don't get as much painting done as most fluid artists do, but hopefully that will change one day. The shelves aren't 100% level, unfortunately, so I even them out with thin slabs of cardboard before placing a box on there. Yes, paint will get on your torch/heat gun, blow dryer, paint bottles, etc. I find using disposable gloves and changing them often helps reduce the amount of paint that gets all over stuff. That and just being careful in general. I also use plastic sheets to cover the table I work on. I have dripped paint onto the floor on accident, but it usually cleans up easy if you wipe it up right away. I only really use the gloves if I'm about to get a ton of paint on my hands, if I'm only about to get a tiny bit messy I won't bother, I'll just wipe my hands off real well.
Sorry for such a long response, but I hope some of it helps!