Atlantic wrote a pretty much perfect post... but just to chime in with a few thoughts as someone about to start framing this weekend for the first time...
(yes I know this post is older... but maybe it will help others reading)
1. Go to your local city hall should you be in a larger locale and get the permits necessary. Ask the inspector there the specifics of what you have to follow re: building code. My inspector told me code is to attach vapor barrier to the concrete "cold wall" at ground level, not at the top. That was a good tip... the book I had read told me otherwise.
2. Draw everything out on paper... EVERYTHING. This helps you think things through and raises confidence. Takes an hour but as a first-timer will help.
3. Start on the least visible wall first.

Make your framing mistakes there and then work outwards.
4. Corners use the 5-4-3 rule. 4' down 1 wall, 3' down the other and then the line that connects them should be 5' long. Give or take an inch you have 2 straight walls and a perfect corner

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