Seed stitch and moss stitch are sometimes the same, and sometimes moss stitch uses two stitches and two rows. I think it depends on what side of the Atlantic you're on.
For your seed stitch, you purl the knits and knit the purls as they face you.
Regardless of whether or not you have an even or odd number of stitches, just remember that for seed stitch, if you end with a purl, start with a purl. If you end with a knit, start with a knit.