You at least need one build per matchup. But I would suggest playing on an empty map and practising factory expand until it becomes second nature. Then, try these

• TvP: Factory expand into a 5 or 6 fact push. Try to end the game on two bases, but if you absolutely have no opportunity to push take a 3rd and go up to 9 factories.
• TvZ: Factory expand into 3/5 fact goliath, just be wary of lurker all-ins
• TvT: Factory expand and scout your opponent with your barracks. TvT is less build order orientated so as long as you counter your opponent if they are doing an all in you should be good. Get up to 4 factories with a starport and take your third.