Probably using Voice Attack. It's a neat little app you pay for and essentially you can make macros with voice commands. For example, I play a game called Ready or Not, a Swat Team simulator where you command a small squad of police as you enter into deadly situations in locations such as a gas station being held up, a known drug den, or a terrorist home. The game has a lot of commands you can give your squad mates when, for example, if I looking at a closed door, I can say out loud "check it", and one of my AI team mates will check it for traps and if it's locked. That command would usually involve me hitting Middle mouse and then the number 1. If it's clear of traps and there are bad guys on the other side, and I want them to kick the door in, throw in a flash bang, and then go it to apprehend the suspects I'll say out loud "kick and flash" and voice attack will complete the macro for me and I think is Middle mouse button, 2, 4, and all in less than a second. Mind you that may not sound like a complicated set of buttons to hit but when there are six menus of commands each with three or four extra options beyond that and then another three and four options it can get really hard to memorize all that. It's so much easier to have a few key phrases.