Topic: Any info on how to make a HDD bootable?

Guys, please I need an urgent help on how to (I mean step-by-step) procedure on how to make a bootable external HDD. The situation is like this, my laptop runs on Linux and hence i cant run some windows-based applications on it and i want to use my external HDD to boot windows, so any useful information on how to go about this will be highly appreciated. Please treat as urgent

Guy, y make ur external HDD bootable when you can dual boot your system, making windows and linux run on it. that's what i do...i run ubuntu and vista on my system presently. you need info u cn call me on 08030794302....no charge @ all.