This is the fun bit, where you create your home in your mind. If you take your time here, and get as many different ideas as you can, you're less likely to say "I wish I'd thought of that before we started". Spend time visiting show homes, home shows and open homes; especially of homes similar to what you're planning to build. Look at how other people have approached their bathrooms, kitchens and outdoor areas.
Always carry a camera. When you see something you like, take a picture.
Find out which builders and architects have good reputations for the type of home you have in mind. Visit them, and ask them if you can look at houses they have designed.
Buy design magazines, clip out photos of rooms you like and put them in a scrapbook with a section for each different part of the house. You will start to see a trend after a little while, and that trend is what you really like.
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