My share;
- put things in there that are in the exact area you want to apply
(like gameplay, a.i., tools or what you are applying too)
- be a specialist on that 1 area, "most studios" don't want an overall coder who can do everything a bit, better a star/ talent in 1 area
- do as if the portfolio has been sent to you, what would you think about it/ mis/ leave out/ want to see better