The clueless thread starter strikes again! Moderators, feel free to move!
Here's a handy tutorial to get you all started making flags for your country.
1. Color. Pick out two or three colors that represent what you want your flag to mean. Here is a handy guide to the significance of colors, their moods and the heraldric symbology:
http://www.color-wheel-pro.com/color-meaning.html2. Think of what you want your flag to represent. If you know the history of your country, who would have had the flag designed? the flag represents his vision of the country, not what it is centuries later. Was it wealthy and powerful? Did it have many provinces? What was the main export? Use these elements to come up with some symbols for your flag. (Crown, stars, grain, etc.)
3. Pick out a motto. (optional) You can use one in english or latin, or if your country has it's own language or writing system use that. Here is a list of common mottos:
http://www.heraldryandcrests.com/Mottos.htm4. Put it all together. The most important color is going to be your background. The other colors usually match your symbols. (wheat is gold, leaves are green, etc.) Try to pick colors that coordinate to an extent. Flags usually employ two or three colors.
5. Be creative. You don't have to have a solid background, look into the meanings of stripes or crests. Invent a seal and use that. Maybe your country has a checkered background. Try not to make your flag too cluttered, simplicity is usually best for identifying a nation's flag in battle.
Have fun! Feel free to post your results, or your own suggestions here.
(Disclaimer: I'm pretty clueless at making flags, but I've been assembling information all night and thought it might be helpful to share.

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