How do I learn how to properly use a Nikon sb600 flash alone with my D70 & D100 shotting manual?

Question

I get either underexposed or overeposed pics, especially when shotting indoors with low light.

Answer 1

There's a bar graph on back of the flash that will tell you how far the subject should be, and what fotoace said.
Nikon has a video for sell on the SB28, I know it's a different model but the fundamentals are the same.
http://www.nikonmall.com/product.asp?sku=2197780&deptcatid=27&searchcat=Educational%2BProducts%253E&searchcatid=4