Sherwin Williams. I definitely recommend the Sherwin Williams. Get them to mix the color for you custom. Also, don't add traction enhancer (sand, basically) unless you are doing more than one coat. It's too sandpaper-y and ends up being more difficult to keep clean. I've never done the flakes but honestly I prefer the look without flakes.

If the room is over 600sqft I'd probably get help, but you can do it yourself. You just have to be quick or the epoxy will start to thicken. For prep I wouldn't worry about etching unless the floor has gotten greasy in the past.

Tape around all the edges of the room with 2" tape so you can work fast. Use a brush to first cut in all the edges 6" and get into any cracks where the roller won't. An 18" wide roller is worth the investment because it allows you to work quickly. If this was a garage or non air conditioned space I would say do it in the evening as things are cooling down so the concrete is "inhaling" and the risk of getting bubbles is less.