Firstly, make sure you are famliar with all of the General Tips (section 5 of Drunky's guide). In terms of saving time the 3rd, 5th and 6th points will probably be of most use to you. If you are simply following the walkthrough guide as is, just make sure that you always pause the game to find out what to do next rather than just letting it run - you could be losing some valuable time there.
Also, simply watching some of the above videos should help even though there isn't one for this mission at the moment. He does a good job of explaining what he's doing, e.g. turning power off to help save money or pre-selecting the facility that he will be placing down next.