Reax stains are unique metallic salt based formulations which are non acidic and work by reacting with various compnants in and on the concrete surface. They produce a widely varied, mottled surface that is permanent and cannot be wiped off or removed like a water base stain. The effects are similar to that of an acid stain but without the extensive cleanup to that process.
Simply spay on the reax, optionally work it in with a broom, wait a few hours for the color change and then seal it up. You cannot have a much easier process. These are permanent stains, require no neutralizing and have no effect on sealers. They are produced only by Walttools, creators of many great products for decorative concrete.