hi there! i'm a new knitter too - just started in january!
an edge stitch is just something you do (usually at the beginning and end of each row) to create a selvedge, either for decorative reasons, to help the knitting lie flat, or for help when sewing together later.
check out
http://www.chicknits.com/edgestitch.shtmlfor more help and good luck on the bikini!
cheers![/url]