Need some help w/pattern

I have been crocheting for only a little while, and I have learned quite a few stitches and how to work with different threads. I thought I was ready for a larger project, so I got a pattern for a cardigan, but there are things they are saying in the pattern that I do not quite understand.
Some of the terms are:
"The instructions between asterisks represent one pattern repeat"

"achieve the correct gauge of 1 pattern
repeat to 3 inches."


"Divide yoke into body and sleeve sections"

"..Rejoin yarn to 7th (6th, 7th, 6th) Ch..."

Any help I would appreciate. Thanks!! ^_^